Surface-treated copper foil, copper foil with carrier, substrate, resin substrate, printed wiring board, copper clad laminate and method for producing printed wiring board

ABSTRACT

A surface-treated copper foil is capable of imparting the profile shape of the substrate surface after removal of the copper foil, the profile shape maintaining fine wiring formability and achieving satisfactory adhesion of electroless copper plating coating. A resin substrate is provided with a profile shape of the surface maintaining fine wiring formability and achieving satisfactory adhesion of electroless copper plating coating. The surface-treated copper foil has a surface-treated layer formed on a copper foil, and the surface roughness Sz of the surface of the surface-treated layer is 2 to 6 μm.

CROSS-REFERENCE TO RELATED APPLICATION

This Application is a divisional of application Ser. No. 14/907,478,filed on 25 Jan. 2016 by Ishii et al., now U.S. Pat. No. ______, whichis a national stage of PCT/JP 2014/069489, filed on 23 Jul. 2014. Thewhole content of those applications is incorporated herein by referenceas if set forth explicitly herein. This application claims benefit ofJapanese Applications Nos. 2013-153010 and 2013-153014, filed on 23 Jul.2013, and 2013-160827 and 2013-160828, filed on 1 Aug. 2013.

TECHNICAL FIELD

The present invention relates to a surface-treated copper foil, a copperfoil with carrier, a substrate, a resin substrate, a printed wiringboard, a copper clad laminate and a method for producing a printedwiring board.

As the method for forming circuits of a semiconductor package substrateand a printed wiring board, a subtractive method is predominantly used.However, recently, due to high integration of semiconductors,miniaturization has been advanced in the circuits of semiconductorpackage substrates and printed wiring boards used for highly integratedsemiconductors, and accordingly it has been becoming difficult to formfine circuits on the basis of subtractive methods.

As measures for forming further finer wirings, the following methodshave been attracting attention: a circuit forming method (1) in whichpattern copper plating is performed by using an ultra-thin copper foilas a power feeding layer, and finally the ultra-thin copper layer isremoved by flash etching to form wirings; a circuit forming method (2)in which a prepreg or a build-up film is cured by vacuum pressing or thelike, the surface of the cured material is roughened to form appropriateasperities on the surface of a substrate, and thus reliable fine wiringsare formed on the substrate surface; and a circuit forming method (3) inwhich a surface profile of a copper foil is transferred to the surfaceof a substrate to form appropriate asperities on the substrate surface,and thus reliable fine airings are formed on the substrate surface.These methods are each generally referred to as a SAP (semi-additiveprocess).

A SAP using the surface profile of a copper foil is described in, forexample, Patent Literature 1. Examples of a typical SAP using such asurface profile of a copper foil includes the following. Specifically,here is quoted a method in which a copper foil laminated on a resin issubjected to an entire-surface etching, the etched surface of asubstrate is subjected to hole opening, the hole-opening portions andthe entire surface or part of the surface of the substrate are subjectedto desmear treatment, a dry film is bonded to the etched surface of thehole opening portions, the dry film on the portions in which no circuitis formed is exposed and developed, the unnecessary portion of the dryfilm is removed with a chemical solution, electroless copper plating andelectric copper plating are applied to the etched substrate surfacehaving no coating dry film and having the copper foil surface profiletransferred thereto, and finally the electroless copper plating layer isremoved by flash etching to form fine wirings.

CITATION LIST Patent Literature

Japanese Patent Laid-Open No. 2006-196863

SUMMARY OF INVENTION Technical Problem

For forming fine wirings, it is preferable that the profile of thesubstrate surface be small and smooth; however, in such a case, theadhesion of the electroless copper plating coating is weak, and thereliability demanded for semiconductor package substrates or printedwiring boards is liable to be impaired. On the other hand, in order toensure the adhesion of the electroless copper plating coating, it ispreferable that the profile of the substrate surface be large; however,in such a case, fine wiring formability is liable to be impaired.

With these respects, the conventional technology has not yet performedsufficient investigation, to leave room for improvement. Accordingly,the present invention takes it as its object to provide asurface-treated copper foil capable of imparting the profile shape ofthe substrate surface after removal of the copper foil, the profileshape maintaining fine wiring formability and achieving satisfactoryadhesion of electroless copper plating coating, and/or a resin substrateprovided with such a profile shape of the surface thereof.

Solution to Problem

In order to achieve the above-described object, the present inventorscontinuously made a diligent study, and have consequently discoveredthat a surface-treated copper foil in which the surface roughness (themaximum height of the surface) Sz of the surface of a surface-treatedlayer is controlled so as to fall within a predetermined range is used,the surface-treated copper foil concerned is bonded to a substrate onwhich circuits are to be formed, then the surface-treated copper foil isremoved, and thus, it is possible to provide a profile shape of thesubstrate surface after removal of the copper foil, the profile shapemaintaining the fine wiring formability and achieving satisfactoryadhesion of electroless copper plating coating. In addition, the presentinventors have discovered that by using a resin substrate in which thesurface roughness (the maximum height of the surface) Sz of the surfaceis controlled so as to fall within a predetermined range, the finewiring formability can be maintained and the satisfactory adhesion ofthe electroless copper plating coating can be achieved, during formingcircuits on the resin substrate surface.

The present invention has been perfected on the basis of theabove-described discovery, and an aspect of the present invention is asurface-treated copper foil, wherein a surface treated layer is formedon a copper foil, and the surface roughness Sz of the surface of thesurface-treated layer is 2 to 6 μm.

In an embodiment, the surface-treated copper foil of the presentinvention is a surface-treated copper foil, wherein a surface-treatedlayer is formed on a copper foil, and the ratio B/A of thethree-dimensional surface area B to the two-dimensional surface area Aof the surface of the surface-treated layer is 1.05 to 1.8.

In another embodiment, in the surface-treated copper foil of the presentinvention, when the surface-treated copper foil is bonded, via thesurface-treated layer side thereof, to a resin substrate and thesurface-treated copper foil is removed, the surface roughness Sz of thesurface, on the copper foil removal side, of the resin substrate is 1 to5 μm.

In yet another embodiment, in the surface-treated copper foil of thepresent invention, when the surface-treated copper foil is bonded, viathe surface-treated layer side thereof, to a resin substrate and thesurface-treated copper foil is removed, the ratio B/A of thethree-dimensional surface area B to the two-dimensional surface area Aof the surface, on the copper foil removal side, of the resin substrateis 1.01 to 1.5.

In yet another embodiment, in the surface-treated copper foil of thepresent invention, when the surface-treated copper foil is bonded, viathe surface-treated layer side thereof, to a resin substrate and thesurface-treated copper foil is removed, the black area rate of thesurface, on the copper foil removal side, of the resin substrate is 10to 50%, and the average value of the diameters of the holes of thesurface, on the copper foil removal side, of the resin substrate is 0.03to 1.0 μm.

In another embodiment, the surface-treated copper foil of the presentinvention is a surface-treated copper foil having a surface-treatedlayer formed on a copper foil, wherein the ratio B/A of thethree-dimensional surface area B to the two-dimensional surface area Aof the surface of the surface-treated layer is 1.05 to 1.8.

In yet another embodiment, in the surface-treated copper foil of thepresent invention, when the surface-treated copper foil is bonded, viathe surface-treated layer side thereof, to a resin substrate and thesurface-treated copper foil is removed, the surface roughness Sz of thesurface, on the copper foil removal side, of the resin substrate is 1 to5 μm.

In yet another embodiment, in the surface-treated copper foil of thepresent invention, when the surface-treated copper foil is bonded, viathe surface-treated layer side thereof, to a resin substrate and thesurface-treated copper foil is removed, the ratio B/A of thethree-dimensional surface area B to the two-dimensional surface area Aof the surface, on the copper foil removal side, of the resin substrateis 1.01 to 1.5.

In yet another embodiment, in the surface-treated copper foil of thepresent invention, when the surface-treated copper foil is bonded, viathe surface-treated layer side thereof, to the resin substrate and thesurface-treated copper foil is removed, the black area rate of thesurface, on the copper foil removal side, of the resin substrate is 10to 50%, and the average value of the diameters of the holes of thesurface, on the copper foil removal side, of the resin substrate is 0.03to 1.0 μm.

In yet another aspect, the surface-treated copper foil of the presentinvention is a surface-treated copper foil, wherein when thesurface-treated copper foil is bonded, via the surface-treated layerside thereof, to a resin substrate and the surface-treated copper foilis removed, the surface roughness Sz of the surface, on the copper foilremoval side, of the resin substrate is 1 to 5 μm.

In yet another embodiment, in the surface-treated copper foil of thepresent invention, when the surface-treated copper foil is bonded, viathe surface-treated layer side thereof, to a resin substrate and thesurface-treated copper foil is removed, the ratio B/A of thethree-dimensional surface area B to the two-dimensional surface area Aof the surface, on the copper foil removal side, of the resin substrateis 1.01 to 1.5.

In yet another embodiment, in the surface-treated copper foil of thepresent invention, when the surface-treated copper foil is bonded, viathe surface-treated layer side thereof, to a resin substrate and thesurface-treated copper foil is removed, the black area rate of thesurface, on the copper foil removal side, of the resin substrate is 10to 50%, and the average value of the diameters of the holes of thesurface, on the copper foil removal side, of the resin substrate is 0.03to 1.0 μm.

In yet another aspect, the present invention is a surface-treated copperfoil, wherein when the surface-treated copper foil is bonded, via thesurface-treated layer side thereof, to a resin substrate and thesurface-treated copper foil is removed, the ratio B/A of thethree-dimensional surface area B to the two-dimensional surface area Aof the surface, on the copper foil removal side, of the resin substrateis 1.01 to 1.5.

In yet another embodiment in the present invention, when thesurface-treated copper foil is bonded, via the surface-treated layerside thereof, to a resin substrate and the surface-treated copper foilis removed, the black area rate of the surface, on the copper foilremoval side, of the resin substrate is 10 to 50%, and the average valueof the diameters of the holes of the surface, on the copper foil removalside, of the resin substrate is 0.03 to 1.0 μm.

In yet another aspect, the present invention is a surface-treated copperfoil, wherein when the surface-treated copper foil is bonded, via thesurface-treated layer side thereof, to a resin substrate and thesurface-treated copper foil is removed, the black area rate of thesurface, on the copper foil removal side, of the resin substrate is 10to 50%, and the average value of the diameters of the holes of thesurface, on the copper foil removal side, of the resin substrate is 0.03to 1.0 μm.

In yet another embodiment, in the surface-treated copper foil of thepresent invention, the surface-treated layer is a roughening-treatedlayer.

In yet another embodiment, in the surface-treated copper foil of thepresent invention, the roughening-treated layer is a layer composed of asingle substance selected from or an alloy including one or moreselected from the group consisting of copper, nickel, cobalt,phosphorus, tungsten, arsenic, molybdenum, chromium and zinc.

In yet another embodiment, the surface-treated copper foil of thepresent invention has, on the surface of the roughening-treated layer,one or more layers selected from the group consisting of a heatresistant layer, a rust-preventing layer, a chromate-treated layer and asilane coupling treated layer.

In a yet another embodiment, in the surface-treated copper foil of thepresent invention, the surface-treated layer is one or more layersselected from the group consisting of a roughening-treated layer, a heatresistant layer, a rust-preventing layer, a chromate-treated layer and asilane coupling treated layer.

In a yet another embodiment, the surface-treated copper foil of thepresent invention is provided with a resin layer on the surface-treatedlayer.

In yet another aspect, the present invention is a copper foil withcarrier, including a carrier, an intermediate layer and an ultra-thincopper layer in this order, wherein the ultra-thin copper layer is thesurface-treated copper foil of the present invention.

In an embodiment, the copper foil with carrier of the present inventionincludes the ultra-thin copper layer on each of both surfaces of thecarrier.

In another embodiment, the copper foil with carrier of the presentinvention includes a roughening-treated layer on the side opposite tothe ultra-thin copper layer of the carrier.

In yet another aspect, the present invention is a substrate prepared bybonding the surface-treated copper foil of the present invention, viathe surface-treated layer side thereof, to a substrate, and by removingthe surface-treated copper foil, wherein the surface roughness Sz of thesurface, on the copper foil removal side, of the substrate is 1 to 5 μm.

In yet another aspect, the present invention is a substrate prepared bybonding the copper foil with carrier of the present invention, via theultra-thin copper layer side thereof, to a substrate, by removing thecarrier from the copper foil with carrier, and by then removing theultra-thin copper layer, being the surface-treated copper foil, whereinthe surface roughness Sz of the surface, on the copper foil removalside, of the substrate is 1 to 5 pin.

In yet another aspect, the present invention is a substrate prepared bybonding the surface-treated copper foil of the present invention, viathe surface-treated layer side thereof, to a substrate, and by removingthe surface-treated copper foil, wherein the ratio B/A of thethree-dimensional surface area B to the two-dimensional surface area Aof surface, on the copper foil removal side, of the substrate is 1.01 to1.5.

In yet another aspect, the present invention is a substrate prepared bybonding the copper foil with carrier of the present invention, via theultra-thin copper layer side thereof, to a substrate, by removing thecarrier from the copper foil with carrier, and by then removing theultra-thin copper layer, being the surface-treated copper foil, whereinthe ratio B/A of the three-dimensional surface area B to thetwo-dimensional surface area A of surface, on the copper foil removalside, of the substrate is 1.01 to 1.5.

In yet another aspect, the present invention is a substrate prepared bybonding the surface-treated copper foil of the present invention, viathe surface-treated layer side thereof, to a substrate, and by removingthe surface-treated copper foil, wherein the black area rate of thesurface, on the copper foil removal side, of the substrate is 10 to50%/o, and the average value of the diameters of the holes of thesurface, on the copper foil removal side, of the substrate is 0.03 to1.0 μm.

In yet another aspect, the present invention is a substrate prepared bybonding the copper foil with carrier of the present invention, via theultra-thin copper layer side thereof, to a substrate, by removing thecarrier from the copper foil with carrier, and by then removing theultra-thin copper layer, being the surface-treated copper foil, whereinthe black area rate of the surface, on the copper foil removal side, ofthe substrate is 10 to 50%, and the average value of the diameters ofthe holes of the surface, on the copper foil removal side, of thesubstrate is 0.03 to 1.0 μm.

In yet another aspect, the present invention is a copper clad laminateproduced by using the surface-treated copper foil of the presentinvention, or the copper foil with carrier of the present invention.

In yet another aspect, the present invention is a printed wiring boardproduced by using the surface-treated copper foil of the presentinvention, or the copper foil with carrier of the present invention.

In yet another aspect, the present invention is an electronic deviceusing the printed wiring board of the present invention.

In yet another aspect, the present invention is a method for producing aprinted wiring board, including:

-   -   a step of preparing the surface-treated copper foil of the        present invention and an insulating substrate;    -   a step of laminating the surface-treated copper foil, via the        surface-treated layer side thereof, on the insulating substrate;    -   a step of removing the surface-treated copper foil on the        insulating substrate; and    -   a step of forming a circuit on the surface of the insulating        substrate with the surface-treated copper foil removed        therefrom.

In yet another aspect, the present invention is a method for producing aprinted wiring board, including:

-   -   a step of preparing the copper foil with carrier of the present        invention and an insulating substrate;    -   a step of laminating the copper foil with carrier, via the        ultra-thin copper layer side thereof, on the insulating        substrate;    -   a step of peeling the carrier of the copper foil with carrier        after laminating the copper foil with carrier and the insulating        substrate on each other;    -   a step of removing the ultra-thin copper layer on the insulating        substrate after peeling the carrier; and    -   a step of forming a circuit on the surface of the insulating        substrate with the ultra-thin copper layer removed therefrom.

In yet another aspect, the present invention is a method for producing aprinted wiring board, including:

-   -   a step of preparing the surface-treated copper foil of the        present invention and an insulating substrate;    -   a step of forming a copper clad laminate by laminating the        surface-treated copper foil, via the surface-treated layer side        thereof, on the insulating substrate; and    -   a step of subsequently forming a circuit by a semi-additive        method, a subtractive method, a partly additive method or a        modified semi-additive method.

In yet another aspect, the present invention is a method for producing aprinted wiring board, including:

-   -   a step of preparing the copper foil with carrier of the present        invention and an insulating substrate;    -   a step of laminating the copper foil with carrier, via the        ultra-thin copper layer side thereof, on the insulating        substrate;    -   a step of forming a copper clad laminate by passing through a        step of peeling the carrier of the copper foil with carrier        after laminating the copper foil with carrier and the insulating        substrate on each other; and    -   a step of subsequently forming a circuit by a semi-additive        method, a subtractive method, a partly additive method or a        modified semi-additive method.

In yet another aspect, the present invention is a method for producing aprinted wiring board, including:

-   -   a step of preparing the surface-treated copper foil of the        present invention, with a circuit formed on the surface thereof        on the surface-treated layer formed side, or the copper foil        with carrier of the present invention, with a circuit formed on        the surface thereof on the ultra-thin copper layer side;    -   a step of forming a resin layer on the surface of the        surface-treated copper foil or the surface of the copper foil        with carrier so as for the circuit to be embedded;    -   a step of forming a circuit on the surface of the resin layer;        and    -   a step of exposing the circuit embedded in the resin layer by        removing the surface-treated copper foil or the copper foil with        carrier.

In yet another aspect, the present invention is a method for producing aprinted wiring board, including:

-   -   a step of preparing a metal foil with a circuit formed on the        surface thereof, or a first surface-treated copper foil being        the surface-treated copper foil of the present invention with a        circuit formed on the surface thereof on the surface-treated        layer formed side, or a metal foil with carrier with a circuit        formed on the surface thereof on the ultra-thin metal layer        side, or a first copper foil with carrier being the copper foil        with carrier of the present invention with a circuit formed on        the surface thereof on the ultra-thin copper layer side;    -   a step of forming a resin layer on the surface of the metal        foil, the surface of the surface-treated copper foil, the        surface of the metal foil with carrier, or the surface of the        copper foil with carrier so as for the circuit to be embedded;    -   a step of laminating a second surface-treated copper foil being        the surface-treated copper foil of the present invention, via        the surface-treated layer side thereof, on the resin layer, or a        step of laminating a second copper foil with carrier being the        copper foil with carrier of the present invention, via the        ultra-thin copper layer side thereof, on the resin layer;    -   a step of peeling the carrier of the second copper foil with        carrier, in the case where the foil laminated on the resin layer        is the second copper foil with carrier;    -   a step of removing the surface-treated copper foil on the resin        layer, or the ultra-thin copper layer remaining after peeling        the carrier of the second copper foil with carrier;    -   a step of forming a circuit on the surface of the resin layer        with the surface-treated copper foil removed therefrom, or on        the surface of the resin layer with the ultra-thin copper layer        removed therefrom; and    -   a step of exposing the circuit embedded in the resin layer after        forming the circuit on the resin layer, by removing the metal        foil or the first surface-treated copper foil, or by removing        the ultra-thin metal layer after peeling the carrier of the        metal foil with carrier, or by removing the ultra-thin copper        layer after peeling the carrier of the first copper foil with        carrier.

In yet another aspect, the present invention is a method for producing aprinted wiring board, including:

-   -   a step of preparing the surface-treated copper foil of the        present invention with a circuit formed on the surface thereof        on the surface-treated layer formed side, or the copper foil        with carrier of the present invention with a circuit formed on        the surface thereof on the ultra-thin copper layer side;    -   a step of forming a resin layer on the surface of the        surface-treated copper foil or the surface of the copper foil        with carrier so as for the circuit to be embedded;    -   a step of laminating a metal foil on the resin layer, or a step        of laminating a metal foil with carrier, via the ultra-thin        copper layer side thereof, on the resin layer;    -   a step of peeling the carrier of the metal foil with carrier, in        the case where the foil laminated on the resin layer is the        metal foil with carrier;    -   a step of removing the metal foil on the resin layer, or the        ultra-thin metal layer remaining after peeling the carrier of        the metal foil with carrier;    -   a step of forming a circuit on the surface of the resin layer        with the metal foil removed therefrom, or the surface of the        resin layer with the ultra-thin copper layer removed therefrom;        and    -   a step of exposing the circuit embedded in the resin layer        circuit after forming the circuit on the resin layer, by        removing the surface-treated copper foil, or by removing the        ultra-thin copper layer after peeling the carrier of the copper        foil with carrier.

In yet another aspect, the present invention is a method for producing aprinted wiring board, including:

-   -   a step of preparing a metal foil with a circuit formed on the        surface thereof, or a first surface-treated copper foil being        the surface-treated copper foil of the present invention with a        circuit formed on the surface thereof on the surface-treated        layer formed side, or a metal foil with carrier with a circuit        formed on the surface thereof on the ultra-thin metal layer        side, or a first copper foil with carrier being the copper foil        with carrier of the present invention with a circuit formed on        the surface thereof on the ultra-thin copper layer side;    -   a step of forming a resin layer on the surface of the metal        foil, or the surface of the surface-treated copper foil, or the        surface of the metal foil with carrier, or the surface of the        copper foil with carrier so as for the circuit to be embedded;    -   a step of laminating a second surface-treated copper foil being        the surface-treated copper foil of the present invention, via        the surface-treated layer side thereof, on the resin layer, or a        step of laminating a second copper foil with carrier being the        copper foil with carrier of the present invention, via the        ultra-thin copper layer side thereof, on the resin layer;    -   a step of peeling the carrier of the second copper foil with        carrier, in the case where the foil laminated on the resin layer        is the second copper foil with carrier;    -   a step of forming a circuit on the resin layer, by using the        surface-treated copper foil on the resin layer, or the        ultra-thin copper layer remaining after peeling the carrier of        the second copper foil with carrier, by a semi-additive method,        a subtractive method, a partly additive method or a modified        semi-additive method; and    -   a step of exposing the circuit embedded in the resin layer after        forming the circuit on the resin layer, by removing the metal        foil or by removing the first surface-treated copper foil, or by        removing the ultra-thin metal layer after peeling the carrier of        the metal foil with carrier, or by removing the ultra-thin        copper layer after peeling the carrier of the first copper foil        with carrier.

In yet another aspect, the present invention is a method for producing aprinted wiring board, including:

-   -   a step of preparing the surface-treated copper foil of the        present invention with a circuit formed on the surface thereof        on the surface-treated layer formed side, or the copper foil        with carrier of the present invention with a circuit formed on        the surface thereof on the ultra-thin copper layer side;    -   a step of forming a resin layer on the surface of the        surface-treated copper foil or the surface of the copper foil        with carrier so as for the circuit to be embedded;    -   a step of laminating a metal foil on the resin layer, or a step        of laminating a metal foil with carrier, via the ultra-thin        copper layer side thereof, on the resin layer;    -   a step of peeling the carrier of the metal foil with carrier, in        the case where the foil laminated on the resin layer is the        metal foil with carrier;    -   a step of forming a circuit on the resin layer by using the        metal foil on the resin layer, or the ultra-thin metal layer        remaining after peeling the carrier of the metal foil with        carrier, by a semi-additive method, a subtractive method, a        partly additive method or a modified semi-additive method; and    -   a step of exposing the circuit embedded in the resin layer after        forming the circuit on the resin layer, by removing the        surface-treated copper foil, or by removing the ultra-thin        copper layer after peeling the carrier of the copper foil with        carrier.

In yet another aspect, the present invention is a resin substrate of thepresent invention having a surface roughness Sz of 1 to 5 μm.

In an embodiment, in the resin substrate of the present invention, theratio B/A of the three-dimensional surface area B to the two-dimensionalsurface area A of the surface is 1.01 to 1.5.

In another embodiment, in the resin substrate of the present invention,the black area rate of the surface is 10 to 50%, and the average valueof the diameters of the holes of the surface is 0.03 to 1.0 μm.

In yet another aspect, the present invention is a resin substrate havingthe ratio B/A of the three-dimensional surface area B to thetwo-dimensional surface area A of the surface of 1.01 to 1.5.

In yet another aspect, the present invention is a resin substrate havingthe black area rate of the surface of 10 to 50%, and the average valueof the diameters of the holes of the surface of 0.03 to 1.0 μm.

In yet another embodiment, the resin substrate of present invention hasthe black area rate of the surface of 10 to 50%, and the average valueof the diameters of the holes of the surface of 0.03 to 1.0 μm.

In yet another embodiment, the resin substrate of present invention isfor use in the semi-additive method.

In yet another aspect, the present invention is a printed wiring boardproduced by using the resin substrate of the present invention.

In yet another aspect, the present invention is a copper clad laminateproduced by using the resin substrate of the present invention.

In yet another aspect, the present invention is a method for producing aprinted wiring board, including:

-   -   a step of preparing a surface-treated copper foil and a resin        substrate;    -   a step of laminating the surface-treated copper foil, via the        surface-treated layer side thereof, on the resin substrate;    -   a step of obtaining the resin substrate of the present invention        by removing the surface-treated copper foil on the resin        substrate; and    -   a step of forming a circuit on the surface of the resin        substrate with the surface-treated copper foil removed        therefrom.

In yet another aspect, the present invention is a method for producing aprinted wiring board, including:

-   -   a step of preparing a copper foil with carrier constituted by        laminating a carrier, an intermediate layer and an ultra-thin        copper layer in this order, and a resin substrate;    -   a step of laminating the copper foil with carrier, via the        ultra-thin copper layer side thereof, on the resin substrate;    -   a step of peeling the carrier of the copper foil with carrier        after laminating the copper foil with carrier and the resin        substrate on each other;    -   a step of obtaining the resin substrate of the present invention        by removing the ultra-thin copper layer on the resin substrate        after peeling the carrier; and    -   a step of forming a circuit on the surface of the resin        substrate with the ultra-thin copper layer removed therefrom.

In yet another aspect, the present invention is a method for producing aprinted wiring board, including: a step of forming a circuit, afterforming a copper clad laminate by laminating a surface-treated copperfoil via the surface-treated layer side thereof, on the resin substrateof the present invention, by a semi-additive method, a subtractivemethod, a partly additive method or a modified semi-additive method.

In yet another aspect, the present invention is a method for producing aprinted wiring board, including:

-   -   a step of laminating a copper foil with carrier constituted by        laminating a carrier, an intermediate layer and an ultra-thin        copper layer in this order, via the ultra-thin copper layer side        thereof, on the resin substrate of the present invention;    -   a step of forming a copper clad laminate by passing through a        step of peeling the carrier of the copper foil with carrier        after laminating the copper foil with carrier and the resin        substrate on each other; and    -   a step of subsequently forming a circuit by a semi-additive        method, a subtractive method, a partly additive method or a        modified semi-additive method.

In yet another aspect, the present invention is a method for producing aprinted wiring board, including:

-   -   a step of preparing a metal foil with a circuit formed on the        surface thereof;    -   a step of forming a resin substrate on the surface of the metal        foil so as for the circuit to be embedded;    -   a step of laminating a surface-treated copper foil, via the        surface-treated layer side thereof, on the resin substrate;    -   a step of obtaining the resin substrate of the present invention        by removing the surface-treated copper foil on the resin        substrate;    -   a step of forming a circuit on the surface of the resin        substrate with the surface-treated copper foil removed        therefrom; and    -   a step of exposing the circuit formed on the surface of the        metal foil and embedded in the resin substrate by removing the        metal foil.

In yet another aspect, the present invention is a method for producing aprinted wiring board, including:

-   -   a step of forming a circuit on the surface on the ultra-thin        copper layer side of a first copper foil with carrier        constituted by laminating a carrier, an intermediate layer and        an ultra-thin copper layer in this order;    -   a step of forming a resin substrate on the surface on the        ultra-thin copper layer side of the first copper foil with        carrier so as for the circuit to be embedded;    -   a step of preparing a second copper foil with carrier        constituted by laminating a carrier, an intermediate layer and        an ultra-thin copper layer in this order, and laminating the        second copper foil with carrier, via the ultra-thin copper layer        side thereof, on the resin substrate;    -   a step of peeling the carrier of the second copper foil with        carrier after laminating the second copper foil with carrier on        the resin substrate;    -   a step of obtaining the resin substrate of the present invention        by removing the ultra-thin copper layer on the resin substrate        after peeling the carrier of the second copper foil with        carrier,    -   a step of forming a circuit on the surface of the resin        substrate with the ultra-thin copper layer removed therefrom;    -   a step of peeling the carrier of the first copper foil with        carrier after forming the circuit on the resin substrate; and    -   a step of exposing the circuit formed on the surface on the        ultra-thin copper layer side of the first copper foil with        carrier and embedded in the resin substrate, by removing the        ultra-thin copper layer of the first copper foil with carrier        after peeling the carrier of the first copper foil with carrier.

In yet another aspect, the present invention is a method for producing aprinted wiring board, including:

-   -   a step of preparing a metal foil with a circuit formed on the        surface thereof;    -   a step of forming the resin substrate of the present invention        on the surface of the metal foil so as for the circuit to be        embedded;    -   a step of laminating a surface-treated copper foil, via the        surface-treated layer side thereof, on the resin substrate, and        forming a circuit on the resin layer by a semi-additive method,        a subtractive method, a partly additive method or a modified        semi-additive method; and    -   a step of exposing the circuit formed on the surface of the        metal foil and embedded in the resin substrate by removing the        metal foil.

In yet another aspect, the present invention is a method for producing aprinted wiring board, including:

-   -   a step of forming a circuit on the surface on the ultra-thin        copper layer side of a first copper foil with carrier        constituted by laminating a carrier, an intermediate layer and        an ultra-thin copper layer in this order;    -   a step of forming the resin substrate of the present invention        on the surface on the ultra-thin copper layer side of the first        copper foil with carrier so as for the circuit to be embedded;    -   a step of preparing a second copper foil with carrier        constituted by laminating a carrier, an intermediate layer and        an ultra-thin copper layer in this order; laminating the second        copper foil with carrier, via the ultra-thin copper layer side        thereof, on the resin substrate and then peeling the carrier of        the second copper foil with carrier; and forming a circuit on        the resin substrate by a semi-additive method, a subtractive        method, a partly additive method or a modified semi-additive        method;    -   a step of peeling the carrier of the first copper foil with        carrier after forming a circuit on the resin substrate; and    -   a step of exposing the circuit formed on the surface on the        ultra-thin copper layer side of the first copper foil with        carrier and embedded in the resin substrate, by removing the        ultra-thin copper layer of the first copper foil with carrier        after peeling the carrier of the first copper foil with carrier.

In yet another aspect, the present invention is a method for producing aprinted wiring board, including:

-   -   a step of preparing a metal foil with a circuit formed on the        surface thereof;    -   a step of forming a resin substrate on the surface of the metal        foil so as for the circuit to be embedded;    -   a step of laminating a copper foil with carrier including a        carrier, an intermediate layer and an ultra-thin copper layer in        this order, via the surface thereof on the ultra-thin copper        layer side, on the resin substrate;    -   a step of obtaining the resin substrate of the present invention        by removing the ultra-thin copper layer on the resin substrate        after peeling the carrier of the copper foil with carrier;    -   a step of forming a circuit on the surface of the resin        substrate with the ultra-thin copper layer removed therefrom;        and    -   a step of exposing the circuit formed on the surface of the        metal foil and embedded in the resin substrate by removing the        metal foil.

In yet another aspect, the present invention is a method for producing aprinted wiring board, including:

-   -   a step of forming a circuit on the surface on the ultra-thin        copper layer side of a copper foil with carrier including a        carrier, an intermediate layer and an ultra-thin copper layer in        this order;    -   a step of forming a resin substrate on the surface on the        ultra-thin copper layer side of the copper foil with carrier so        as for the circuit to be embedded;    -   a step of laminating a surface-treated copper foil, via the        surface-treated layer side thereof, on the resin substrate;    -   a step of obtaining the resin substrate of the present invention        by removing the surface-treated copper foil on the resin        substrate;    -   a step of forming a circuit on the surface of the resin        substrate with the surface-treated copper foil having been        removed therefrom;    -   a step of peeling the carrier of the copper foil with carrier        after forming a circuit on the resin substrate; and    -   a step of exposing the circuit formed on the surface on the        ultra-thin copper layer side of the copper foil with carrier by        removing the ultra-thin copper layer of the copper foil with        carrier after peeling the carrier of the copper foil with        carrier.

In yet another aspect, the present invention is a method for producing aprinted wiring board, including:

-   -   a step of preparing a metal foil with a circuit formed on the        surface thereof;    -   a step of forming the resin substrate of the present invention        so as for the circuit to be embedded;    -   a step of forming a circuit on the resin substrate; and    -   a step of exposing the circuit formed on the surface of the        metal foil and embedded in the resin substrate by removing the        metal foil.

In yet another aspect, the present invention is a method for producing aprinted wiring board, including:

-   -   a step of forming a circuit on the surface on the ultra-thin        copper layer side of a copper foil with carrier including a        carrier, an intermediate layer and an ultra-thin copper layer in        this order;    -   a step of forming the resin substrate of the present invention        on the surface on the ultra-thin copper layer side of the copper        foil with carrier so as for the circuit to be embedded;    -   a step of forming a circuit on the resin substrate;    -   a step of peeling the carrier of the copper foil with carrier        after forming the circuit on the resin substrate; and    -   a step of exposing the circuit formed on the surface on the        ultra-thin copper layer side of the copper foil with carrier and        embedded in the resin substrate by removing the ultra-thin        copper layer of the copper foil with carrier after peeling the        carrier of the copper foil with carrier.

Advantageous Effects of Invention

According to the present invention, it is possible to provide asurface-treated copper foil capable of imparting a profile shape of thesubstrate surface after removal of the copper foil, capable ofmaintaining fine wiring formability and implementing satisfactoryadhesion of electroless copper plating coating, and a resin substrateprovided with the profile shape of the surface.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 illustrates a schematic example of a semi-additive method usingthe profile of a copper foil.

FIG. 2 illustrates a production flow of samples for obtaining the dataof Examples and Comparative Examples.

FIGS. 3A, 3B, 3C, 3D and 3E show the SEM images (×30000) of the copperfoil-treated surfaces of Examples A1, A2, A3, A5 and A6, respectively.

FIGS. 4A and 4B show the SEM images (×6000) of the copper foil-treatedsurfaces of Comparative Examples A1 and A2.

FIGS. 5(A), 5(B), 5(C), 5(D) and 5(E) show the SEM images (×30000) ofthe surfaces of the resin substrates of Examples A1(B1), A2(B2), A3(B3),A5(B5) and A6(B6), respectively.

FIGS. 6(A) and 6(B) show the SEM images (×6000) of the surfaces of theresin substrates of Comparative Examples A1(B1) and A2(B2),respectively.

DESCRIPTION OF EMBODIMENTS

[Resin Substrate]

The resin substrate according to the present invention is notparticularly limited as long as the resin substrate allows thebelow-described surface shape to be formed; the resin substrateconcerned can be formed with, for example, a prepreg (GHPL-830MBT or thelike) manufactured by Mitsubishi Gas Chemical Company, Inc., a prepreg(679-FG or the like) manufactured by Hitachi Chemical Co., Ltd., and aprepreg (EI-6785TS-F or the like) manufactured by Sumitomo Bakelite Co.,Ltd. In the present invention, the prepreg GHPL-830MBT manufactured byMitsubishi Gas Chemical Company, Inc. was prepared. As the temperature,pressure and time of a laminating press, the conditions recommended bythe substrate maker were used.

The thickness of the resin substrate according to the present inventionis not particularly limited; however, the thickness of the resinsubstrate can be, for example, 750 to 850 μm, 100 to 200 μm, or 30 to100 μm, and is typically 30 to 200 μm (in the case of a double-sidedplate).

[Surface Roughness Sz of Resin Substrate]

In the SAP method, as a method for quantifying the profile shape of asubstrate surface for forming a circuit thereon, the roughnessmeasurement using a contact type roughness meter has hitherto beencommon. On the contrary, in the present invention, it has been foundthat the profile shape of the substrate surface having the surfaceroughness (the maximum height of the surface) Sz as measured with alaser roughness meter, specified to fall within an appropriate rangemaintains more satisfactorily the fine wiring formability and achieves asatisfactory adhesion of the electroless copper plating coating. Fromsuch a viewpoint, the surface roughness Sz of the resin substrateaccording to the present invention is controlled to be 1 to 5 μm. Whenthe surface roughness Sz of the resin substrate surface is less than 1μm, it is difficult to achieve a satisfactory adhesion of theelectroless copper plating coating. When the surface roughness Sz of theresin substrate surface exceeds 5 μm, the fine wiring formability of theresin substrate surface is degraded. The surface roughness Sz of theresin substrate surface is preferably 1 to 4 μm, more preferably 1.5 to3.5 μm, and furthermore preferably 2 to 3 μm.

[Area Ratio B/A of Resin Substrate Surface]

The profile shape of the surface of the resin substrate having the ratiobetween the three-dimensional surface area and the two-dimensionalsurface area falling within a predetermined range is satisfactory in thefine wiring formability and achieves a satisfactory adhesion of theelectroless copper plating coating. From such a viewpoint, the ratio B/Aof the three-dimensional surface area B to the two-dimensional surfacearea A of the surface of the resin substrate according to the presentinvention is preferably controlled to be 1.01 to 1.5. When the ratio B/Aof the three-dimensional surface area B to the two-dimensional surfacearea A of the surface of the resin substrate is less than 1.01, it isdifficult to achieve a satisfactory adhesion of the electroless copperplating coating. When the ratio B/A of the three-dimensional surfacearea B to the two-dimensional surface area A of the surface of the resinsubstrate exceeds 1.5, the fine wiring formability of the surface of theresin substrate is degraded. The ratio B/A of the three-dimensionalsurface area B to the two-dimensional surface area A of the surface ofthe resin substrate according to the present invention is preferably1.03 to 1.4, more preferably 1.05 to 1.35 and furthermore preferably 1.1to 1.3.

[Black Area Rate and Average Value of Diameters of Holes of the Surfaceof Resin Substrate]

When the degree of asperity of the surface of the resin substrate isrepresented by the black area rate obtained from the SEM observationphotograph, the profile shape of the surface of the resin substratehaving the black area rate concerned falling within a predeterminedrange is satisfactory in fine wiring formability, and achieves asatisfactory adhesion of the electroless copper plating coating. Fromsuch a viewpoint, it is preferable that the black area rate of thesurface of the resin substrate according to the present invention becontrolled so as to be 10 to 50%. As the black area rate, black-whiteimage processing was applied to the SEM image (magnification of 30 k) ofthe substrate surface, by using Photo Shop 7.0 software, and thus, thearea rate (%) of the black region concerned was determined. The blackarea rate (%) was determined as the rate at the threshold value of 128by selecting “Histogram” of “Image” found in Photo Shop 7.0. It is to benoted that the black region indicates that the measurement surface isconcave, and the white region indicates that the measurement surface isconvex. When the black area rate concerned of the substrate surface isless than 15%, it is difficult to achieve a satisfactory adhesion of theelectroless copper plating coating. When the black area rate concernedof the substrate surface exceeds 50%, the fine wiring formability isdegraded.

The profile shape of the surface of the resin substrate, having theblack area rate falling within the predetermined range and at the sametime having the average value of the diameters of the holes of thesurface falling within the predetermined range is the necessarycondition for achieving a satisfactory fine wiring formability and asatisfactory adhesion of the electroless copper plating coating. This isbecause only the black area rate does not satisfy the size of theprofile and the appropriate distribution of the profile on the planethereof. From such a viewpoint, it is preferable that the average valueof the diameters of the holes of the surface of the resin substrateaccording to the present invention be controlled so as to be 0.03 to 1.0μm. When the average value of the diameters of the holes concerned ofthe surface of the resin substrate is less than 0.03 μm, it is difficultto achieve a satisfactory adhesion of the electroless copper platingcoating. When the average value of the diameters of the holes concernedof the surface of the resin substrate exceeds 1.0 μm, the fine wiringformability is degraded.

As described above, in the resin substrate according to the presentinvention, it is preferable that the black area rate concerned of thesubstrate surface be 10 to 50% and the average value of the diameters ofthe holes concerned of the substrate surface be 0.03 to 1.0 μm; it ismore preferable that the black area rate be 15 to 45% and the averagevalue of the diameters of the holes be 0.1 to 0.8 μm; and it isfurthermore preferable that the black area rate be 20 to 40% and theaverage value of the diameters of the holes be 0.15 to 0.7 μm.

[Method for Forming Surface Profile of Resin Substrate]

The profile shape of the surface of the resin substrate according to thepresent invention can be formed by laminating a surface-treated copperfoil on the resin substrate and by subsequently removing thesurface-treated copper foil concerned by entire-surface etching or thelike. The profile shape of the surface of the resin substrate accordingto the present invention can also be formed by treating the surface ofthe resin substrate with a predetermined chemical solution.

In the method for forming the surface profile of the resin substrateaccording to the present invention, using a surface-treated copper foil,first there is prepared a surface-treated copper foil controlled so asfor the surface roughness (the maximum height of the surface) Sz of thesurface of the surface-treated layer to be 2 to 6 μm. Next, thesurface-treated copper foil concerned is bonded, via the surface-treatedlayer side thereof, to the resin substrate, and then the surface-treatedcopper foil is removed by entire-surface etching or the like. In thisway, the surface roughness Sz of the surface of the resin substrateafter removing the surface-treated copper foil is 1 to 5 μm.

In the present invention, “the surface of the surface-treated layer”means the outermost surface on the surface-treated side. Specifically,when surface-treated layers such as a roughening-treated layer, arust-preventing layer, a heat resistant layer, a chromate-treated layerand a silane coupling treated layer are provided on a copper foil, thesurface of the surface-treated layer means the surface obtained afterproviding these surface-treated layers concerned on the copper foil.

When as the surface-treated copper foil, a surface-treated copper foilwith the ratio B/A of the three-dimensional surface area B to thetwo-dimensional surface area A of the surface of the surface-treatedlayer controlled to be 1.05 to 1.8 is used and bonded to the resinsubstrate in the same manner as described above, and the surface-treatedcopper foil concerned is removed by entire-surface etching or the like,the ratio B/A of the three-dimensional surface area B to thetwo-dimensional surface area A of the surface of the resin substrateafter removing the surface-treated copper foil is 1.01 to 1.5.

When as the surface-treated copper foil, a surface-treated copper foilhaving a surface roughness Sz as measured with a laser roughness meterof 2 to 6 μm and having the ratio B/A between the three-dimensionalsurface area B and the two-dimensional surface area A controlled to be1.05 to 1.8 is used and bonded to the resin substrate in the same manneras described above, and the surface-treated copper foil concerned isremoved by entire-surface etching or the like, the black area rate ofthe surface of the resin substrate can be controlled to be 10 to 50%,and the average value of the diameters of the holes of the surface ofthe resin substrate can be controlled to be 0.03 to 1.0 μm.

By controlling the current density for surface treatment during thesurface treatment such as during the formation of roughened particlesand the immersion time in a plating solution after the completion of thesurface treatment, the surface state of the copper foil and the form andthe formation density of roughened particles, after the surfacetreatment are determined, and accordingly, the surface roughness Sz, thearea ratio B/A, the black area rate and the average value of thediameters of the holes of the surface-treated copper foil can becontrolled.

Specifically, during the surface treatment such as during the formationof roughened particles, by performing the surface treatment with thecurrent density of the surface treatment controlled to be high, andsuccessively performing the surface treatment with the current densityof the surface treatment controlled to be low, the surface state of thecopper foil and the form and the formation density of roughenedparticles, after the surface treatment are determined, and theabove-described surface roughness Sz, area ratio B/A, black area rateand average value of the diameters of the holes can be controlled. Inaddition, it is also effective to repeatedly perform the operation thatthe surface treatment is performed with the current density of thesurface treatment controlled to be high, and successively the surfacetreatment is performed with the current density of the surface treatmentcontrolled to be low.

Here, when the current density is allowed to be high during the surfacetreatment such as during the formation of roughened particles, thedeposited metal particles tend to grow in a direction perpendicular tothe surface of the copper foil. In addition, when the current density isallowed to be low during the surface treatment such as during theformation of roughened particles, the surface of the copper foil tendsto be smooth (asperities tend to occur to a low degree).

Accordingly, the operation that the surface treatment is performed withthe current density of the surface treatment controlled to be high, andsuccessively the surface treatment is performed with the current densityof the surface treatment controlled to be low is regarded as the surfacestate control such that metal particles are allowed to grow in thedirection perpendicular to the surface of the copper foil, andsubsequently the asperities due to the metal particles and the surfaceof the cooper foil are embedded so as to form a smooth surface.

In addition, when the surface-treated layer of the copper foil is easilydissolved in a plating solution, the effect of the immersion time in theplating solution after the completion of the surface treatment on thesurface form of the surface treated copper foil tends to be moreprofound.

In the method for forming the surface profile (the above-describedsurface roughness Sz, area ratio B/A, black area rate and average valueof the diameters of the holes) of the resin substrate according to thepresent invention, based on a treatment using a chemical solution, thesurface profile can be formed by applying a desmear treatment to theresin substrate under the following immersion treatment conditions A orB, and by subsequently performing a neutralization treatment.

(Desmear Treatment Conditions A)

-   -   Desmear treatment solution: 40 g/L KMnO₄, 20 g/L NaOH    -   Treatment temperature: Room temperature    -   Immersion time: 20 minutes    -   Number of rotations of stirrer: 300 rpm

(Desmear Treatment Conditions B)

-   -   Desmear treatment solution: 90 g/L KMnO₄, 5 g/L HCl    -   Treatment temperature: 49° C.    -   Immersion time: 20 minutes    -   Number of rotations of stirrer: 300 rpm

(Neutralization Treatment Conditions)

-   -   Neutralization treatment solution: L-Ascorbic acid 80 g/L    -   Treatment temperature: Room temperature    -   Immersion time: 3 minutes    -   No stirring

The remainders of the treatment solutions used in the desmear treatment,electrolysis, surface treatment, plating or the like used in the presentinvention are water unless otherwise specified.

In addition to the above-described immersion treatment, by performingshower treatments A and B, and a neutralization treatment on the surfaceof the resin substrate, under the following treatment conditions, it ispossible to perform the formation of the surface profile (the surfaceroughness Sz, area ratio B/A, black area rate, and average value ofdiameters of holes) of the resin substrate in the same manner asdescribed above.

(Shower Treatment Conditions A)

-   -   Desmear treatment solution: 40 g/L KMnO₄, 20 g/L NaOH    -   Treatment temperature: Room temperature    -   Treatment time: 20 minutes    -   Shower pressure: 0.2 MPa

(Shower Treatment Conditions B)

-   -   Desmear treatment solution: 90 g/L KMnO₄, 5 g/L HCl    -   Treatment temperature: 49° C.    -   Treatment time: 20 minutes    -   Shower pressure: 0.2 MPa

(Neutralization Treatment Conditions)

-   -   Neutralization treatment solution: L-Ascorbic acid 80 g/L    -   Treatment temperature: Room temperature    -   Immersion time: 3 minutes    -   No stirring

[Surface-Treated Copper Foil]

The surface-treated copper foil of the present invention can be used forforming the surface profile of the resin substrate. The copper foil usedin the surface-treated copper foil concerned may either be anelectrolytic copper foil or a rolled copper foil. The thickness of thecopper foil concerned is not particularly required to be limited;however, the thickness of the copper foil is, for example, 1 μm or more,2 μm or more, 3 μm or more, or 5 μm or more, and for example, 3000 μm orless, 1500 μm or less, 800 μm or less, 300 μm or less, 150 μm or less,100 μm or less, 70 μm or less, 50 μm or less, or 40 μm or less.

Examples of the rolled copper foil used in the present invention includecopper alloy foils including one or more elements such as Ag, Sn, In,Ti, Zn, Zr, Fe, P, Ni, Si, Te, Cr, Nb, V, B, and Co. When theconcentration of the above-described elements is high (for example, 10%by mass or more in total), the conductivity is sometimes degraded. Theconductivity of the rolled copper foil is preferably 50% IACS or more,more preferably 60% IACS or more, and furthermore preferably 80% IACS ormore. Examples of the rolled copper foil include the copper foilsproduced by using tough pitch copper (JIS H3100 C1100) or oxygen-freecopper (JIS H3100 C1020). It is to be noted that when the term “copperfoil” is used alone in the present specification, the term “copper foil”also includes copper alloy foils.

The electrolytic copper foil usable in the present invention can beprepared with the following electrolyte composition and the followingproduction conditions.

Common Electrolytic Raw Foil:

<Electrolyte Composition>

-   -   Copper: 80 to 120 g/L    -   Sulfuric acid: 80 to 120 g/L    -   Chlorine: 30 to 100 ppm    -   Leveling agent (glue): 0.1 to 10 ppm

Double-Sided Flat Electrolytic Raw Foil, and Ultra-Thin Copper Foil withCarrier:

<Electrolyte Composition>

-   -   Copper: 80 to 120 g/L    -   Sulfuric acid: 80 to 120 g/L    -   Chlorine: 30 to 100 ppm    -   Leveling agent 1 (bis(3-sulfopropyl) disulfide): 10 to 30 ppm    -   Leveling agent 2 (amine compound): 10 to 30 ppm

As the amine compound, an amine compound of the following chemicalformula can be used.

(wherein, in the chemical formula, R₁ and R₂ are each a group selectedfrom the group consisting of a hydroxyalkyl group, an ether group, anaryl group, an aromatic-substituted alkyl group, an unsaturatedhydrocarbon group, and an alkyl group.)

<Production Conditions>

-   -   Current density: 70 to 100 A/dm²    -   Electrolyte temperature: 50 to 65° C.    -   Linear speed of electrolyte: 1.5 to 5 m/sec    -   Electrolysis time: 0.5 to 10 minutes (regulated according to        deposited copper thickness and current density)

As roughening treatment, there can be used alloy platings such ascopper-cobalt-nickel plating, copper-nickel-phosphorus alloy plating,copper-nickel-tungsten alloy plating, and copper-cobalt-tungsten alloyplating; more preferably copper alloy plating can be used. Thecopper-cobalt-nickel alloy plating as the roughening treatment can beimplemented in such a way that ternary alloy layers are formed byelectroplating so as to have the following deposition amounts: 15 to 40mg/dm² of copper, 100 to 3000 μg/dm² of cobalt, and 100 to 1500 μg/dm²of nickel. When the deposition amount of Co is less than 100 μg/dm²,sometimes the heat resistance is degraded and the etching property isalso degraded. When the deposition amount of Co exceeds 3000 μg/dm²,such a deposition amount is not favorable in the case where magneticeffect is required to be considered, sometimes causes etching stain, andsometimes degrades acid resistance and chemical resistance. When thedeposition amount of Ni is less than 100 μg/dm², sometimes heatresistance is degraded. On the other hand, when the deposition amount ofNi exceeds 1500 μg/dm², sometimes etching residue grows. A preferabledeposition amount of Co is 1000 to 2500 μg/dm², and a preferabledeposition amount of nickel is 500 to 1200 μg/dm². Here, the etchingstain means that Co remains undissolved in etching with copper chloride,and the etching residue means that Ni remains undissolved in alkalineetching with ammonium chloride.

The plating bath and plating conditions for forming such a ternarycopper-cobalt-nickel alloy plating are as follows:

Plating bath composition: Cu 10 to 20 g/L, Co 1 to 10 g/L, Ni 1 to 10g/L

pH: 1 to 4

Temperature: 30 to 50° C.

Current density D_(k): 20 to 30 A/dm²

Plating time: 1 to 5 seconds

Immersion time in the same plating solution after completion of plating:20 seconds or less (because immersion longer than 20 seconds disturbsparticle shapes), preferably 10 seconds or less, more preferably 5seconds or less

After completion of the plating, usually the plated product is not takenout from the plating solution particularly in haste; however, in thepresent invention, after the completion of the plating concerned, it isnecessary to take out the plated product from the plating solutionwithin a predetermined time. Accordingly, as described above, theimmersion time in the same plating solution after the completion of theplating is set at 20 seconds or less. When the plated product isimmersed for the immersion time concerned exceeding 20 seconds, theroughened particles are possibly partially dissolved by the platingsolution. The partial dissolution of the roughened particles isconsidered to give a cause for disturbing the particle shapes.

By setting the immersion time in the same plating solution after thecompletion of plating to be as short as 10 seconds or less, or 5 secondsor less, the particle shapes can be less disturbed in an effectivemanner.

In the same manner as in the case of the copper-cobalt-nickel alloyplating, in the case of the alloy plating other than thecopper-cobalt-nickel alloy plating, it is important to control theimmersion time in the same plating solution after the completion of theplating so as to be 20 seconds or less (because immersion longer than 20seconds disturbs particle shapes), preferably 10 seconds or less andmore preferably 5 seconds or less. With the immersion exceeding 20seconds in the immersion time concerned, the plating solution possiblypartially dissolves the roughened particles. Such a partial dissolutionof the roughened particles is considered to be a cause for thedisturbance of the particle shapes. Heretofore known conditions can beused for the pH, temperature, current density, and plating time of thealloy plating other than the copper-cobalt-nickel alloy plating.

By setting the immersion time in the same plating solution after thecompletion of plating to be as short as 10 seconds or less, or 5 secondsor less, the particle shapes can be less disturbed in an effectivemanner.

In addition, a copper plating as the following roughening treatment mayalso be performed as a surface treatment. The surface-treated layerformed by the following copper plating as the roughening treatment ishigh in the copper concentration, and the surface-treated layer becomesa roughening-treated layer (plating layer) mostly constituted withcopper. The roughening-treated layer (plating layer) high in copperconcentration is characterized by being hardly dissolved in the platingsolution. The following copper plating as the roughening treatment isperformed in the order of the copper plating 1 and the copper plating 2.

Copper Plating 1

(Solution Composition 1)

-   -   Cu concentration: 10 to 30 g/L    -   H₂SO₄ concentration: 50 to 150 g/L    -   Tungsten concentration: 0.5 to 50 mg/L    -   Sodium dodecyl sulfate: 0.5 to 50 mg/L

(Electroplating Conditions 1)

-   -   Temperature: 30 to 70° C.

(First Stage Current Conditions)

-   -   Current density: 18 to 70 A/dm²    -   Roughening coulomb quantity: 1.8 to 1000 A/dm², preferably 1.8        to 500 A/dm²    -   Plating time: 0.1 to 20 seconds

(Second Stage Current Conditions)

-   -   Current density: 0.5 to 13 A/dm²    -   Roughening coulomb quantity: 0.05 to 1000 A/dm², preferably 0.05        to 500 A/dm²    -   Plating time: 0.1 to 20 seconds

The first stage and the second stage may be repeated. In addition, afterthe first stage is performed once or a plurality of times, the secondstage may also be performed once or a plurality of times. Alternatively,the following operations may also be repeated: after the first stage isperformed once or a plurality of times, the second stage is performedonce or a plurality of times.

Copper Plating 2

(Solution Composition 2)

-   -   Cu concentration: 20 to 80 g/L    -   H₂SO₄ concentration: 50 to 200 g/L

(Electroplating Conditions 2)

-   -   Temperature: 30 to 70° C.

(Current Conditions)

-   -   Current density: 5 to 50 A/dm²    -   Roughening coulomb quantity: 50 to 300 A/dm²    -   Plating time: 1 to 60 seconds

Alternatively, on the copper foil, an alloy plating such as theabove-described copper-cobalt-nickel alloy plating and theabove-described copper plating may be performed in combination. It ispreferable to perform the above described alloy plating after theabove-described copper plating is performed.

In the present invention, the surface-treated layer formed on the copperfoil may be a roughening-treated layer. The roughening treatment usuallymeans a treatment in which nodular electrodeposition is formed on thesurface of a copper foil after degreasing, specifically on the copperfoil surface adhering to the resin substrate, namely, the surface on thesurface-treated side of the copper foil, for the purpose of improvingthe peel strength of the copper foil after lamination. An electrolyticcopper foil has asperities at the time of production; however, byaugmenting the protrusions of the electrolytic copper foil by rougheningtreatment, the asperities can be further grown. The roughening treatmentcan be performed, for example, by forming roughened particles withcopper or a copper alloy. The roughening treatment may be a refinedtreatment. The roughening-treated layer may be a layer composed of asingle substance selected from or an alloy including one or moreselected from the group consisting of copper, nickel, cobalt,phosphorus, tungsten, arsenic, molybdenum, chromium and zinc.Additionally, after the roughened particles are formed with copper or acopper alloy, it is also possible to further perform a rougheningtreatment in which secondary particles or tertiary particles areprovided with a single substance or an alloy of nickel, cobalt, copperor zinc. Additionally, on the surface of the roughening-treated layer,one or more layers selected from the group consisting of a heatresistant layer, a rust-preventing layer, a chromate-treated layer and asilane coupling treated layer may be formed.

In the present invention, the surface-treated layer formed on the copperfoil may be one or more selected from the group consisting of aroughening-treated layer, a heat resistant layer, a rust-preventinglayer, a chromate-treated layer and a silane coupling treated layer.

As the heat resistant layer and the rust-preventing layer, heretoforeknown heat resistant layers and rust-preventing layers can be used. Forexample, the heat resistant layer and/or the rust-preventing layer maybe a layer including one or more elements selected from the groupconsisting of nickel, zinc, tin, cobalt, molybdenum, copper, tungsten,phosphorus, arsenic, chromium, vanadium, titanium, aluminum, gold,silver, platinum group elements, iron and tantalum; or a metal layer oran alloy layer composed of one or more elements selected from the groupconsisting of nickel, zinc, tin, cobalt, molybdenum, copper, tungsten,phosphorus, arsenic, chromium, vanadium, titanium, aluminum, gold,silver, platinum group elements, iron and tantalum. The heat resistantlayer and/or the rust-preventing layer may also include an oxide, anitride and a silicide including one or more elements selected from thegroup consisting of nickel, zinc, tin, cobalt, molybdenum, copper,tungsten, phosphorus, arsenic, chromium, vanadium, titanium, aluminum,gold, silver, platinum group elements, iron and tantalum. The heatresistant layer and/or the rust-preventing layer may also be a layerincluding a nickel-zinc alloy. The heat resistant layer and/or therust-preventing layer may also be a nickel-zinc alloy layer. Thenickel-zinc alloy layer may be a layer containing 50 wt % to 99 wt % ofnickel and 50 wt % to 1 wt % of zinc, zinc, except for inevitableimpurities. The total deposition amount of zinc and nickel in thenickel-zinc alloy layer may be 5 to 1000 mg/m², preferably 10 to 500mg/m², and preferably 20 to 100 mg/m². The ratio (=deposition amount ofnickel/deposition amount of zinc) between the deposition amount ofnickel and the deposition amount of zinc in the nickel-zincalloy-containing layer or the nickel-zinc alloy layer is preferably 1.5to 10. The deposition amount of nickel in the layer including anickel-zinc alloy or the nickel-zinc alloy layer is preferably 0.5 mg/m²to 500 mg/m², and more preferably 1 mg/m² to 50 mg/m². In the case wherethe heat resistant layer and/or the rust-preventing layer is a layerincluding a nickel-zinc alloy, when the inner wall portion of thethrough-holes, the via holes or the like is brought into contact withthe desmear solution, the interface between the copper foil and theresin substrate is hardly corroded by the desmear solution, and theadhesion between the copper foil and the resin substrate is improved.

For example, the heat resistant layer and/or the rust-preventing layermay be a layer formed by sequentially laminating a nickel or nickelalloy layer having a deposition amount of 1 mg/m² to 100 mg/m²,preferably 5 mg/m² to 50 mg/m² and a tin layer having a depositionamount of 1 mg/m² to 80 mg/m², preferably 5 mg/m² to 40 mg/m², and thenickel alloy layer may be constituted with any one of anickel-molybdenum alloy, a nickel-zinc alloy, and anickel-molybdenum-cobalt alloy. In the heat resistant layer and/or therust-preventing layer, the total deposition amount of nickel or a nickelalloy and tin is preferably 2 mg/m² to 150 mg/m² and more preferably 10mg/m² to 70 mg/m². In the heat resistant layer and/or therust-preventing layer, [nickel deposition amount in the nickel or thenickel alloy]/[tin deposition amount] is preferably 0.25 to 10 and morepreferably 0.33 to 3. By using the heat resistant layer concerned and/orthe rust-preventing layer, after the processing of the copper foil withcarrier into a printed wiring board, the peel strength of the circuit,the degradation rate of the chemical resistance of the peel strengthconcerned and the like are made satisfactory.

For the silane coupling agent used in the silane coupling treatment,heretofore known silane coupling agents may be used; for example, anamino silane coupling agent, an epoxy silane coupling agent, or amercapto silane coupling agent may also be used. As the silane couplingagent, for example, the following compounds may be used:vinyltrimethoxysilane, vinylphenyltrimethoxysilane,γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane,4-glycidylbutyltrimethoxysilane, γ-aminopropyltriethoxysilane,N-β(aminoethyl)-γ-aminopropyltrimethoxysilane,N-3-(4-(3-aminopropoxy)butoxy)propyl-3-aminopropyltrimethoxysilane,imidazolesilane, triazinesilane, and γ-mercaptopropyltrimethoxysilane.

The silane coupling treated layer may be formed by using, for example, asilane coupling agent such as an epoxy silane, an amino silane, amethacryloxy silane and a mercapto silane. Such silane coupling agentsmay also be used as mixtures of two or more thereof. The silane couplingtreated layer is preferably a layer formed by using, among these, anamino silane coupling agent or an epoxy silane coupling agent.

The amino silane coupling agent as referred to herein may be an aminosilane coupling agent selected from the group consisting ofN-(2-aminoethyl)-3-aminopropyltrimethoxysilane,3-(N-styrylmethyl-2-aminoethylamino)propyltrimethoxysilane,3-aminopropyltriethoxysilane,bis(2-hydroxyethyl)-3-aminopropyltriethoxysilane,aminopropyltrimethoxysilane, N-methylaminopropyltrimethoxysilane,N-phenylaminopropyltrimethoxysilane,N-(3-acryloxy-2-hydroxypropyl)-3-aminopropyltriethoxysilane,4-aminobutyltriethoxysilane,(aminoethylaminomethyl)phenetyltrimethoxysilane,N-(2-aminoethyl-3-aminopropyl)trimethoxysilane,N-(2-aminoethyl-3-aminopropyl)tris(2-ethylhexoxy)silane,6-(aminohexylaminopropyl)trimethoxysilane, aminophenyltrimethoxysilane,3-(l-aminopropoxy)-3,3-dimethyl-1-propenyltrimethoxysilane,3-aminopropyltris(methoxyethoxy)silane, 3-aminopropyltriethoxysilane,3-aminopropyltrimethoxysilane, ω-aminoundecyltrimethoxysilane,3-(2-N-benzylaminoethylaminopropyl)trimethoxysilane,bis(2-hydroxyethyl)-3-aminopropyltriethoxysilane,(N,N-diethyl-3-aminopropyl)trimethoxysilane,(N,N-dimethyl-3-aminopropyl)trimethoxysilane,N-methylaminopropyltrimethoxysilane,N-phenylaminopropyltrimethoxysilane,3-(N-styrylmethyl-2-aminoethylamino)propyltrimethoxysilane,γ-aminopropyltriethoxysilane,N-β(aminoethyl)-γ-aminopropyltrimethoxysilane, andN-3-(4-(3-aminopropoxy)butoxy)propyl-3-aminopropyltrimethoxysilane.

It is desirable that the silane coupling treated layer be formed with anarea density falling in the following ranges, in terms of silicon atom:a range from 0.05 mg/m² to 200 mg/m², preferably a range from 0.15 mg/m²to 20 mg/m², and preferably a range from 0.3 mg/m² to 2.0 mg/m². In thecase of the foregoing ranges, the adhesion between the substrate and thesurface-treated copper foil can be more improved.

[Surface Roughness Sz of Surface-Treated Copper Foil]

In the SAP method, as a method for quantifying the profile shape of asubstrate surface for forming a circuit thereon, the roughnessmeasurement using a contact type roughness meter has hitherto beencommon. On the contrary, in the present invention, it has been foundthat the profile shape of the substrate surface having the surfaceroughness (the maximum height of the surface) Sz as measured with alaser roughness meter, specified to fall within an appropriate rangemaintains more satisfactorily the fine wiring formability and achieves asatisfactory adhesion of the electroless copper plating coating. Fromsuch a viewpoint, in the surface-treated copper foil according to thepresent invention, the surface roughness Sz of the surface of thesurface-treated layer is controlled to be 2 to 6 μm. Due to the surfaceroughness Sz of the surface of the surface-treated layer controlled tobe 2 to 6 μm, after the surface-treated copper foil concerned is bonded,via the surface-treated layer side thereof, to the substrate, and thenthe surface-treated copper foil is removed from the substrate, thesurface roughness Sz of the surface, on the copper foil removal side, ofthe substrate is 1 to 5 μm. When the surface roughness Sz of the surfaceof the surface-treated layer of the surface-treated copper foil is lessthan 2 μm, after the surface-treated copper foil concerned is bonded,via the surface-treated layer side thereof, to substrate, and then thesurface-treated copper foil is removed from the substrate, the surfaceroughness Sz of the surface, on the copper foil removal side, of thesubstrate is less than 1 μm, and it is difficult to achieve thesatisfactory adhesion of the electroless copper plating coating. Whenthe surface roughness Sz of the surface of the surface-treated layer ofthe surface-treated copper foil exceeds 6 μm, after the surface-treatedcopper foil concerned is bonded, via the surface-treated layer sidethereof, to substrate, and then the surface-treated copper foil isremoved from the substrate, the surface roughness Sz of the surface, onthe copper foil removal side, of the substrate exceeds 5 μm, and thefine wiring formability is degraded. The surface roughness Sz of thesurface of the surface-treated layer of the surface-treated copper foilaccording to the present invention is preferably 2 to 5.5 μm, morepreferably 2.5 to 5.5 μm and furthermore preferably 3 to 5 μm. Thesurface roughness Sz of the substrate surface after the removal of thesurface-treated copper foil according to the present invention ispreferably 1 to 4 μm, more preferably 1.5 to 3.5 μm and furthermorepreferably 2 to 3 μm.

[Area Ratio B/A of Surface-Treated Copper Foil]

The ratio B/A of the three-dimensional surface area B to thetwo-dimensional surface area A of the surface on the surface-treatedside of the surface-treated copper foil significantly affects theprofile shape of the surface of the substrate after the surface-treatedcopper foil concerned is bonded, via the surface-treated layer sidethereof, to the substrate, and the surface-treated copper foil isremoved. From such a viewpoint, it is preferable that in thesurface-treated copper foil according to the present invention, theratio B/A of the three-dimensional surface area B to the two-dimensionalsurface area A of the surface of the surface-treated layer be controlledto be 1.05 to 1.8. The ratio B/A of the three-dimensional surface area Bto the two-dimensional surface area A of the surface on thesurface-treated side can also be said, for example in the case where thesurface concerned is roughening-treated, as the ratio B/A of the surfacearea B of the roughened particles to the area A obtained when the copperfoil is plan-viewed from the copper foil surface side. Due to the ratioB/A of the three-dimensional surface area B to the two-dimensionalsurface area A of the surface on the surface-treated side of thesurface-treated copper foil controlled to be 1.05 to 1.8, after thesurface-treated copper foil concerned is bonded, via the surface-treatedlayer side thereof, to the substrate, and then the surface-treatedcopper foil is removed from the substrate, the ratio B/A of thethree-dimensional surface area B to the two-dimensional surface area Aof the surface, on the copper foil removal side, of the substrate is1.01 to 1.5. When the ratio B/A of the three-dimensional surface area Bto the two-dimensional surface area A of the surface on thesurface-treated side of the surface-treated copper foil is less than1.05, after the surface-treated copper foil concerned is bonded, via thesurface-treated layer side thereof, to the substrate, and then thesurface-treated copper foil is removed from the substrate, the ratio B/Aof the three-dimensional surface area B to the two-dimensional surfacearea A of the surface, on the copper foil removal side, of the substrateis less than 1.01, and it is difficult to achieve the satisfactoryadhesion of the electroless copper plating coating. When the ratio B/Aof the three-dimensional surface area B to the two-dimensional surfacearea A of the surface on the surface-treated side of the surface-treatedcopper foil exceeds 1.8, after the surface-treated copper foil concernedis bonded, via the surface-treated layer side thereof, to substrate, andthen the surface-treated copper foil is removed from the substrate, theratio B/A of the three-dimensional surface area B to the two-dimensionalsurface area A of the surface, on the copper foil removal side, of thesubstrate exceeds 1.5, and the fine wiring formability is degraded. Theratio B/A of the three-dimensional surface area B to the two-dimensionalsurface area A of the surface on the surface-treated side of thesurface-treated copper foil according to the present invention ispreferably 1.10 to 1.75, more preferably 1.14 to 1.71 and furthermorepreferably 1.18 to 1.67. The ratio B/A of the three-dimensional surfacearea B to the two-dimensional surface area A of the substrate surfaceafter removal of the surface-treated copper foil according to thepresent invention is preferably 1.03 to 1.4, more preferably 1.05 to1.35 and furthermore preferably 1.1 to 1.3.

[Black Area Rate and Average Value of Diameters of Holes ofSurface-Treated Copper Foil]

When the degree of asperity of the substrate surface is represented bythe black area rate obtained from the SEM observation photograph, theprofile shape of the surface of the substrate having the black area rateconcerned falling within a predetermined range is satisfactory in finewiring formability, and achieves a satisfactory adhesion of theelectroless copper plating coating. From such a viewpoint, it ispreferable that in the surface-treated copper foil according to thepresent invention, when the surface-treated copper foil is bonded, viathe surface-treated layer side thereof, to the substrate, and then thesurface-treated copper foil is removed, the black area rate of thesurface, on the copper foil removal side, of the substrate be controlledto be 10 to 50%. As the black area rate, black-white image processingwas applied to the SEM image (magnification of 30 k) of the substratesurface, by using Photo Shop 7.0 software, and thus, the area rate (%)of the black region concerned was determined. The black area rate (%)was determined as the rate at the threshold value of 128 by selecting“Histogram” of “Image” found in Photo Shop 7.0. It is to be noted thatthe black region indicates that the measurement surface is concave, andthe white region indicates that the measurement surface is convex. Whenthe black area rate concerned of the substrate surface is less than 10%,it is difficult to achieve a satisfactory adhesion of the electrolesscopper plating coating. When the black area rate concerned of thesubstrate surface exceeds 50%, the fine wiring formability is degraded.

The profile shape of the surface of the resin substrate, having theblack area rate falling within the predetermined range and at the sametime having the average value of the diameters of the holes of thesurface falling within the predetermined range is the necessarycondition for achieving a satisfactory fine wiring formability and asatisfactory adhesion of the electroless copper plating coating. This isbecause only the black area rate does not satisfy the size of theprofile and the appropriate distribution of the profile on the planethereof. From such a viewpoint, the average value of the diameters ofthe holes of the surface of the resin substrate according to the presentinvention is controlled so as to be 0.03 to 1.0 μm. When the averagevalue of the diameters of the holes concerned of the surface of theresin substrate is less than 0.03 μm, it is difficult to achieve asatisfactory adhesion of the electroless copper plating coating. Whenthe average value of the diameters of the holes concerned of the surfaceof the resin substrate exceeds 1.0 μm, the fine wiring formability isdegraded.

As described above, in the resin substrate according to the presentinvention, it is preferable that the black area rate concerned of thesubstrate surface be 10 to 50% and the average value of the diameters ofthe holes concerned of the substrate surface be 0.03 to 1.0 μm; it ismore preferable that the black area rate be 15 to 45% and the averagevalue of the diameters of the holes be 0.1 to 0.8 μm; and it isfurthermore preferable that the black area rate be 20 to 40% and theaverage value of the diameters of the holes be 0.15 to 0.7 μm.

By controlling the current density for surface treatment during thesurface treatment such as during the formation of roughened particlesand the immersion time in a plating solution after the completion of thesurface treatment, the surface state of the copper foil and the form andthe formation density of roughened particles, after the surfacetreatment are determined, and the surface roughness Sz, the area ratioB/A, the black area rate and the average value of the diameters of theholes of the surface-treated copper foil can be controlled.

Specifically, during the surface treatment such as during the formationof roughened particles, by performing the surface treatment with thecurrent density of the surface treatment controlled to be high, andsuccessively performing the surface treatment with the current densityof the surface treatment controlled to be low, the surface state of thecopper foil and the form and the formation density of roughenedparticles, after the surface treatment are determined, and theabove-described surface roughness Sz, area ratio B/A, black area rateand average value of the diameters of the holes can be controlled. Inaddition, it is also effective to repeatedly perform the operation thatthe surface treatment is performed with the current density of thesurface treatment controlled to be high, and successively the surfacetreatment is performed with the current density of the surface treatmentcontrolled to be low.

Here, when the current density is allowed to be high during the surfacetreatment such as during the formation of roughened particles, thedeposited metal particles tend to grow in a direction perpendicular tothe surface of the copper foil. In addition, when the current density isallowed to be low during the surface treatment such as during theformation of roughened particles, the surface of the copper foil tendsto be smooth (asperities tend to occur to a low degree).

Accordingly, the operation that the surface treatment is performed withthe current density of the surface treatment controlled to be high, andsuccessively the surface treatment is performed with the current densityof the surface treatment controlled to be low is regarded as the surfacestate control such that metal particles are allowed to grow in thedirection perpendicular to the surface of the copper foil, andsubsequently the asperities due to the metal particles and the surfaceof the cooper foil are embedded so as to form a smooth surface.

In addition, when the surface-treated layer of the copper foil is easilydissolved in a plating solution, the effect of the immersion time in theplating solution after the completion of the surface treatment on thesurface form of the surface treated copper foil tends to be moreprofound.

[Copper Foil with Carrier]

As the surface-treated copper foil according to the present invention, acopper foil with carrier may also be used. The copper foil with carrierincludes a carrier, an intermediate layer laminated on the carrier, andan ultra-thin copper layer laminated on the intermediate layer.Alternatively, the copper foil with carrier may include a carrier, anintermediate layer and an ultra-thin copper layer, in this order. Thecopper foil with carrier may have a surface-treated layer such as aroughening-treated layer on one of or each of both of the surface on thecarrier side and the surface on the ultra-thin copper layer side.

In the case where a roughening-treated layer is provided on the surfaceon the carrier side of the copper foil with carrier, when the copperfoil with carrier is laminated, via the surface side thereof on thecarrier side concerned, on s support such as a resin substrate, thecopper foil with carrier has an advantage that the carrier and thesupport such as a substrate are hardly peeled from each other.

<Carrier>

In the present invention, a metal foil can be used as a carrier. As themetal foil, copper foil, copper alloy foil, nickel foil, nickel alloyfoil, aluminum foil, aluminum alloy foil, iron foil, iron alloy foil,stainless steel foil, zinc foil, zinc alloy foil and the like can beused. Among these, as the carrier, from the viewpoint of the easiness informing a release layer, it is particularly preferable to use copperfoil. The carrier is typically provided in the form of a rolled copperfoil or an electrolytic copper foil. In general, electrolytic copperfoil is produced by electrolytically depositing copper on a titanium orstainless steel drum from a copper sulfate plating bath, and rolledcopper foil is produced by repeating plastic working and heat treatmentwith a rolling roll. As the material for the copper foil, there can beused, in addition to high purity copper such as tough pitch copper andoxygen-free copper, for example, Sn-containing copper, Ag-containingcopper, copper alloy with Cr, Zr, Mg or the like added thereto, andcopper alloys such as Corson alloys with Ni, Si and the like addedthereto.

The thickness of the carrier usable in the present invention is notparticularly limited; the thickness concerned can be appropriatelyregulated to be a thickness suitable for achieving the role as thecarrier, and the thickness concerned is allowed to be 12 μm or more.However, the thickness concerned is too thick, the production cost isincreased, and hence, in general, it is preferable to set the thicknessto be 35 μm or less. Accordingly, the thickness of the carrier istypically 12 to 70 μm, and more typically 18 to 35 μm.

<Intermediate Layer>

On the carrier, the intermediate layer is provided. Between the carrierand the intermediate layer, another layer may be provided. Theintermediate layer used in the present invention is not particularlylimited as long as the intermediate layer has a constitution such thatthe ultra-thin copper layer is hardly peeled from the carrier before thestep of laminating the copper foil with carrier on the insulatingsubstrate, and on the other hand, after the step of laminating on theinsulating substrate, the ultra-thin copper layer is allowed to bepeeled from the carrier. For example, the intermediate layer of thecopper foil with carrier of the present invention may include one or twoor more selected from the group consisting of Cr, Ni, Co, Fe, Mo, Ti, W,P, Cu, Al, Zn, alloys of these, hydrates of these, oxides of these andorganic substances. In addition, the intermediate layer maybe composedof two or more layers.

For example, the intermediate layer can be constituted by forming, fromthe carrier side, a single metal layer composed of one element selectedfrom the element group constituted with one element selected from thegroup consisting of Cr, Ni, Co, Fe, Mo, Ti, W, P, Cu, Al and Zn, or analloy layer composed of one or two or more elements selected from theelement group consisting of Cr, Ni, Co, Fe, Mo, Ti, W, P, Cu, Al and Zn,and by forming, on the single metal layer of the alloy layer, a layercomposed of hydrates or oxides of one or two or more elements selectedfrom the element group consisting of Cr, Ni, Co, Fe, Mo, Ti, W, P, Cu,Al and Zn.

In addition, for example, the intermediate layer can be constituted bylaminating, on the carrier, nickel, a nickel-phosphorus alloy or anickel-cobalt alloy, and chromium in this order. The adhesion betweennickel and copper is higher than the adhesion between chromium andcopper, and hence, when the ultra-thin copper layer is peeled, peelingoccurs between the ultra-thin copper layer and chromium. For the nickelin the intermediate layer, the barrier effect to prevent the diffusionof the copper component from the carrier to the ultra-thin copper layeris expected. The deposition amount of nickel in the intermediate layeris preferably 100 μg/dm² or more and 40000 μg/dm² or less, morepreferably 100 μg/dm² or more and 4000 μg/dm² or less, more preferably100 μg/dm² or more and 2500 μg/dm² or less, and more preferably 100μg/dm² or more and 1000 g/dm² or less; the deposition amount of chromiumin the intermediate layer is preferably 5 μg/dm² or more and 100 μg/dm²or less. When the intermediate layer is provided only on one side, it ispreferable to provide a rust-preventing layer such as a Ni plating layercarrier on the opposite side of the carrier. On both sides of thecarrier, the intermediate layers may also be provided.

<Ultra-Thin Copper Layer>

On the intermediate layer, the ultra-thin copper layer is provided.Another layer may also be provided between the intermediate layer andthe ultra-thin copper layer. The ultra-thin copper layer concerned isthe surface-treated copper foil of the present invention. The thicknessof the ultra-thin copper layer is not particularly limited, but isgenerally thinner than the carrier, and for example, 12 μm or less. Thethickness of the ultra-thin copper layer is typically 0.5 to 12 μm andmore typically 1.5 to 5 μm. In addition, before the ultra-thin copperlayer is provided on the intermediate layer, a strike plating using acopper-phosphorus alloy may be performed in order to reduce thepin-holes of the ultra-thin copper layer. For the strike plating, forexample, a copper pyrophosphate plating solution may be cited. On bothsides of the carrier, ultra-thin copper layers may also be provided.

[Resin Layer on Surface-Treated Layer]

A resin layer may also be provided on the surface-treated layer of thesurface-treated copper foil of the present invention. The resin layermay be an insulating resin layer.

The resin layer may be an adhesive, or an insulating resin layer of asemi-cured state (B stage state) for adhesion. The semi-cured state (Bstage state) includes a state in which no sticky feeling is sensed whenthe finger is in contact with the surface, the insulating resin layercan be stored in a state of being superposed, and moreover, curingreaction occurs when undergoing heat treatment.

The resin layer may include a thermocuring resin or may be athermoplastic resin. The resin layer may include a thermoplastic resin.The type of the above-described resin is not particularly limited;examples of the suitable resins include: epoxy resin, polyimide resin,multifunctional cyanic acid ester compound, maleimide compound,maleimide-based resin, polyvinylacetal resin, urethane resin, polyethersulfone, polyether sulfone resin, aromatic polyamide resin,polyamideimide resin, rubber-modified epoxy resin, phenoxy resin,carboxyl group-modified acrylonitrile-butadiene resin, polyphenyleneoxide, bismaleimide triazine resin, thermocuring polyphenylene oxideresin, cyanate ester-based resin, and polybasic carboxylic acidanhydride-containing resin. The resin layer may be a resin layerincluding a block copolymerized polyimide resin layer, or a resin layerincluding a block copolymerized polyimide resin and a polymaleimidecompound. The epoxy resin can be used without causing any particularproblem as long as the epoxy resin has two or more epoxy groups in themolecule thereof, and can be used for the application toelectric-electronic material. The epoxy resin is preferably an epoxyresin obtained by epoxidation by using a compound having two or moreglycidyl groups in the molecule of the compound. As the epoxy resin, oneor mixtures of two or more selected from the group consisting ofbisphenol A-type epoxy resin, bisphenol F-type epoxy resin, bisphenolS-type epoxy resin, bisphenol AD-type epoxy resin, novolac type epoxyresin, cresol novolac type epoxy resin, alicyclic epoxy resin,brominated epoxy resin, glycidylamine-type epoxy resin, triglycidylisocyanurate, glycidylamine compounds such as N,N-diglycidylaniline,glycidyl ester compounds such as tetrahydrophthalic acid diglycidylester, phosphorus-containing epoxy resin, biphenyl-type epoxy resin,biphenyl novolac type epoxy resin, tris-hydroxyphenylmethane-type epoxyresin, and tetraphenyl methane-type epoxy resin; or alternatively, thehydrogenated products or the halogenated products of the above-describedepoxy resins can also be used.

The resin layer may include heretofore known resins, resin curingagents, compounds, curing promoters, dielectrics (any dielectrics suchas dielectrics including inorganic compounds and/or organic compounds,or dielectrics including metal oxides may be used), reaction catalysts,cross-linking agents, polymers, prepregs, skeletal materials and thelike. The resin layer may be formed by using the substances (resins,resin curing agents, compounds, curing promoters, dielectrics, reactioncatalysts, cross-linking agents, polymers, prepregs, skeletal materialsand the like) and/or the methods for forming resin layers, and theapparatuses for forming resin layers described in the followingdocuments: International Publication No. WO 2008/004399, InternationalPublication No. WO 2008/053878, International Publication No. WO2009/084533, Japanese Patent Laid-Open No. 11-5828, Japanese PatentLaid-Open No. 11-140281, Japanese Patent No. 3184485, InternationalPublication No. WO 97/02728, Japanese Patent No. 3676375, JapanesePatent Laid-Open No. 2000-43188, Japanese Patent No. 3612594, JapanesePatent Laid-Open No. 2002-179772, Japanese Patent Laid-Open No.2002-359444, Japanese Patent Laid-Open No. 2003-304068, Japanese PatentNo. 3992225, Japanese Patent Laid-Open No. 2003-249739, Japanese PatentNo. 4136509, Japanese Patent Laid-Open No. 2004-82687, Japanese PatentNo. 4025177, Japanese Patent Laid-Open No. 2004-349654, Japanese PatentNo. 4286060, Japanese Patent Laid-Open No. 2005-262506, Japanese PatentNo. 4570070, Japanese Patent Laid-Open No. 2005-53218, Japanese PatentNo. 3949676, Japanese Patent No. 4178415, International Publication No.WO 2004/005588, Japanese Patent Laid-Open No. 2006-257153, JapanesePatent Laid-Open No. 2007-326923, Japanese Patent Laid-Open No.2008-111169, Japanese Patent No. 5024930, International Publication No.WO 2006/028207, Japanese Patent No. 4828427, Japanese Patent Laid-OpenNo. 2009-67029, International Publication No. WO 2006/134868, JapanesePatent No. 5046927, Japanese Patent Laid-Open No. 2009-173017,International Publication No. WO 2007/105635, Japanese Patent No.5180815, International Publication No. WO 2008/114858, InternationalPublication No. WO 2009/008471, Japanese Patent Laid-Open No.2011-14727, International Publication No. WO 2009/001850, InternationalPublication No. WO 2009/145179, International Publication No. WO2011/068157, Japanese Patent Laid-Open No. 2013-19056.

Resin solutions are prepared by dissolving these resins in the solventssuch as methyl ethyl ketone (MEK), cyclopentanone, dimethyl formamide,dimethyl acetamide, N-methylpyrrolidone, toluene, methanol, ethanol,propylene glycol monomethyl ether, dimethyl formamide, dimethylacetamide, cyclohexanone, ethyl cellosolve, N-methyl-2-pyrrolidone,N,N-dimethyl acetamide, and N,N-dimethyl formamide; these resinsolutions are applied to the ultra-thin copper layer, or the heatresistant layer, the rust-preventing layer, the chromate-treated layer,or the silane coupling agent layer by, for example, a roll coatermethod, successively heat-dried, if necessary, to remove the solvent toform a B-stage state. For the drying, for example, a hot air dryingfurnace may be used, and the drying temperature may be 100 to 250° C.,and preferably 130 to 200° C. The composition of the resin layer may bedissolve by using a solvent, to prepare a resin solution having a resinsolid content of 3 wt % to 60 wt %, preferably 10 wt % to 40 wt %, andmore preferably 25 wt % to 40 wt %. The dissolution by using a mixedsolvent composed of methyl ethyl ketone and cyclopentanone is motpreferable at the present stage from an environmental viewpoint.

The surface-treated copper foil provided with the resin layer(surface-treated copper foil with resin) is used in a mode in which theresin layer of the copper foil is superposed on the substrate, then thewhole is thermally compression bonded to thermally cure the resin layer,and successively a predetermined wiring pattern is formed on the copperfoil. For the copper foil with carrier using the surface-treated copperfoil concerned as the ultra-thin copper layer, the copper foil withcarrier provided with the resin layer (copper foil with carrier withresin) is used in a mode in which the resin layer of the copper foil issuperposed on the substrate, then the whole is thermally compressionbonded to thermally cure the resin layer, successively the carrier ispeeled to expose the ultra-thin copper layer (naturally, the exposedface is the surface on the intermediate layer side of the ultra-thincopper layer), and a predetermined wiring patter is formed on theexposed ultra-thin copper layer.

When the surface-treated copper foil with resin or the copper foil withresin and carrier is used, it is possible to reduce the number of sheetsof prepreg material used during the production of a multilayer printedwiring board. Moreover, it is possible to produce a copper clad laminatewhen the thickness of the resin layer is allowed to be a thicknesscapable of ensuring interlayer insulation, or even when no prepregmaterial is used at all. In this case, it is also possible to furtherimprove the smoothness of the surface of the substrate by undercoatingan insulating resin on the surface of the substrate.

When no prepreg material is used, the material cost for the prepregmaterial can be saved, the laminating step is made simple, thus,economic advantage is provided, the thickness of the produced multilayerprinted wiring board is made thinner by the thickness of the prepregmaterial, and in particular, in the case of a copper foil with resin andcarrier, there is provided an advantage that an ultra-thin multilayerprinted wiring board having a thickness of one layer of 100 μm or lesscan be produced. The thickness of the resin layer concerned ispreferably 0.1 to 120 μm.

When the thickness of the resin layer is thinner than 0.1 μm, theadhesion is degraded; when the surface-treated copper foil with resin orthe copper foil with resin and carrier is laminated on a substratehaving an inner layer material, it is sometimes difficult to ensure theinter layer insulation with the circuit of the inner layer material. Thetotal resin layer thickness of the cured resin layer and the semi-curedresin layer is preferably 0.1 μm to 120 μm and practically preferably 35μm to 120 μm. In such a case, it is preferable that the thickness of thecured resin layer be 5 to 20 μm, and the thickness of the semi-curedresin layer be 15 to 115 μm. This is because when the total resin layerthickness exceeds 120 μm, it is sometimes difficult to produce a thinmultilayer printed wiring board; and when the total resin layerthickness is less than 35 μm, although it is easy to form a thinmultilayer printed wiring board, the resin layer as the insulating layerbetween the circuits in the inner layers is too thin, and the insulationbetween the circuits of the inner layers sometimes tends to be madeunstable. When the thickness of the cured resin layer is less than 5 μm,it is sometimes necessary to consider the surface roughness degree ofthe roughened surface of the copper foil. On the contrary, when thethickness of the cured resin layer exceeds 20 μm, the effect due to thecured resin layer is sometimes not particularly improved, and the totalthickness is thick. The cured resin layer may be 3 μm to 30 μm inthickness. The semi-cured resin layer may be 7 μm to 55 μm in thickness.The total thickness of the cured resin layer and the semi-cured resinlayer may be 10 μm to 60 μm.

When the surface-treated copper foil with resin or the copper foil withresin and carrier is used in the production of an ultra-thin multilayerprinted wiring board, it is preferable for the purpose of reducing thethickness of the multilayer printed wiring board that the thickness ofthe resin layer be set to be 0.1 μm to 5 μm, more preferably 0.5 μm to 5μm, and more preferably 1 μm to 5 μm. When the thickness of the resinlayer is set to be 0.1 μm to 5 μm, in order to improve the adhesionbetween the resin layer and the copper foil, after a heat resistantlayer and/or a rust-preventing layer and/or a chromate-treated layerand/or a silane coupling treated layer is provided on thesurface-treated layer, it is preferable to form a resin layer on theheat resistant layer or the rust-preventing layer or thechromate-treated layer or the silane coupling treated layer.

When the resin layer includes a dielectric, the thickness of the resinlayer is preferably 0.1 to 50 μm, preferably 0.5 μm to 25 μm, and morepreferably 1.0 μm to 15 μm. The thickness of the resin layer means anaverage value of the thickness values measured at optional 10 points bycross-sectional observation.

On the other hand, when the thickness of the resin layer is made thickerthan 120 μm, it is difficult to form a resin layer having the intendedthickness by one step of application, and thus extraneous material costand extraneous number of steps are needed to be economicallydisadvantageous. Moreover, the formed resin layer is poor inflexibility, cracks or the like tend to occur during handling the resinlayer, and smooth lamination is sometimes made difficult due to theoccurrence of excessive resin flow during the thermal compressionbonding to the inner layer material.

Moreover, as another product form of the copper foil with resin andcarrier, it is also possible to produce in a form of a copper foil withresin, without including the carrier, by coating a resin layer on theultra-thin copper layer, or the heat resistant layer, or therust-preventing layer, or the chromate-treated layer, or the silanecoupling treated layer, by converting the resin layer into a semi-curedstate, and by successively peeling the carrier.

Hereinafter, several examples of the production process of the printedwiring board using the resin substrate according to the presentinvention. A printed circuit board is completed by mounting electroniccomponents on the printed wiring board.

An embodiment of the method for producing a printed wiring boardaccording to the present invention, using a semi-additive methodincludes: a step of preparing a surface-treated copper foil and a resinsubstrate; a step of laminating the surface-treated copper foil, via thesurface-treated layer side thereof, on the resin substrate; a step ofobtaining the resin substrate of the present invention by removing thesurface-treated copper foil on the resin substrate; and a step offorming a circuit on the surface of the resin substrate with thesurface-treated copper foil removed therefrom.

FIG. 1 illustrates a schematic example of a semi-additive method usingthe profile of a copper foil. In the method concerned, the surfaceprofile of the copper foil is used for the formation of the surfaceprofile of the resin substrate. Specifically, first, a copper cladlaminate is prepared by laminating the copper foil of the presentinvention on the resin substrate. Next, the copper foil of the copperclad laminate is subjected to entire-surface etching. Next, electrolesscopper plating is applied to the surface of the resin substrate(entire-surface etched substrate) with the surface profile of the copperfoil transferred thereon. Then, the portion, free from formation ofcircuit, of the resin substrate (entire-surface etched substrate) iscoated with a dry film or the like, and electro (electrolytic) copperplating is applied to the surface, not coated with the dry film, of theelectroless copper plating layer. Subsequently, after the dry film isremoved, the electroless copper plating formed on the portion free fromformation of circuit is removed to form a fine circuit. The fine circuitformed in the present invention adheres to the etched surface of theresin substrate (entire-surface etched substrate) with the surfaceprofile of the copper foil of the present invention transferred thereon,and hence the adhesion (peel strength) of the fine circuit is madesatisfactory.

The resin substrate can be a resin substrate incorporating an innerlayer circuit. In the present invention, the semi-additive method meansa method in which thin electroless plating and/or electrolytic platingis applied on a resin substrate or a copper foil seed layer, and afterthe formation of a pattern, a conductor pattern is formed by usingelectroplating or etching. For electroless plating and/or electrolyticplating, copper plating can be used. As the method for forming copperplating, heretofore known methods can be used.

An embodiment of the method for producing a printed wiring boardaccording to the present invention, using the semi-additive methodincludes: a step of preparing a copper foil with carrier and a resinsubstrate; a step of laminating the copper foil with carrier, via theultra-thin copper layer side thereof, to the resin substrate; a step ofpeeling the carrier of the copper foil with carrier after the copperfoil with carrier and the resin substrate are laminated on each other; astep of obtaining the resin substrate of the present invention byremoving the ultra-thin copper layer on the resin substrate afterpeeling the carrier; and a step of forming a circuit on the surface ofthe resin substrate with the ultra-thin copper layer removed therefrom.

In the present invention, the semi-additive method means a method inwhich thin electroless plating is applied on an insulating substrate ora copper foil seed layer, subsequently electrolytic plating is performedif necessary, further subsequently, after formation of a pattern, aconductor pattern is formed by using electroplating and etching.

An embodiment of the method for producing a printed wiring boardaccording to the present invention, using a semi-additive methodincludes: a step of preparing a copper foil with carrier and aninsulating substrate; a step of laminating the copper foil with carrier,via the ultra-thin copper layer side thereof, on the insulatingsubstrate; a step of peeling the carrier of the copper foil with carrierafter laminating the copper foil with carrier and the insulatingsubstrate on each other; a step of removing the ultra-thin copper layeron the insulating substrate after peeling the carrier; and a step offorming a circuit on the surface of the insulating substrate with theultra-thin copper layer removed therefrom.

An embodiment of the method for producing a printed wiring boardaccording to the present invention includes a step of laminating asurface-treated copper foil, via the surface-treated layer side thereof,on the resin substrate of the present invention to form a copper cladlaminate, and then forming a circuit by a semi-additive method, asubtractive method, a partly additive method or a modified semi-additivemethod.

An embodiment of the method for producing a printed wiring boardaccording to the present invention includes: a step of preparing thesurface-treated copper foil and an insulating substrate; and a step oflaminating the surface-treated copper foil. via the surface-treatedlayer side thereof, on the insulating substrate to form a copper cladlaminate, and then forming a circuit by a semi-additive method, asubtractive method, a partly additive method or a modified semi-additivemethod.

In the present invention, the subtractive method means a method in whichthe unnecessary portion of the copper foil on the copper clad laminateis selectively removed by etching or the like to form a conductorpattern.

In the present invention, the partly additive method means a method inwhich catalyst nuclei are imparted on a substrate including a conductorlayer, and including, if necessary, pierced holes for through-holes orvia holes, and the substrate is etched to form a conductor circuit; andafter a solder resist or a plating resist is provided if necessary,plating up is applied to the through-holes, via holes or the like on theconductor circuit by electroless plating treatment to produce a printedwiring board.

In the present invention, the modified semi-additive method means amethod in which a metal foil is laminated on a resin substrate; thenon-circuit-formation portion is protected with a plating resist, andthe circuit-formation portion is subjected to copper plating up; andthen, the resist is removed and the metal foil on the portion other thanthe circuit-formation portion is removed by (flash) etching to form acircuit on the resin substrate.

An embodiment of the method for producing a printed wiring boardaccording to the present invention includes: a step of laminating acopper foil with carrier, via the ultra-thin copper layer side thereof,on the resin substrate of the present invention; and a step oflaminating the copper foil with carrier and the resin substrate on eachother, then forming a copper clad laminate by passing through a step ofpeeling the carrier of the copper foil with carrier, and then forming acircuit by a semi-additive method, a subtractive method, a partlyadditive method or a modified semi-additive method.

An embodiment of the method for producing a printed wiring boardaccording to the present invention includes: a step of preparing thecopper foil with carrier and the insulating substrate of the presentinvention; a step of laminating the copper foil with carrier, via theultra-thin copper layer side thereof, on the insulating substrate; and astep of laminating the copper foil with carrier and the insulatingsubstrate on each other, then forming a copper clad laminate by passingthrough a step of peeling the carrier of the copper foil with carrier,and then forming a circuit by a semi-additive method, a subtractivemethod, a partly additive method or a modified semi-additive method.

An embodiment of the method for producing a printed wiring boardaccording to the present invention, using the semi-additive method,includes: a step of preparing a metal foil with a circuit formed on thesurface thereof; a step of forming a resin substrate on the surface ofthe metal foil so as for the circuit to be embedded; a step oflaminating a surface-treated copper foil or a copper foil with carrier,via the surface-treated layer side thereof or the ultra-thin copperlayer side, respectively, on the resin substrate; a step of obtainingthe resin substrate of the present invention by removing thesurface-treated copper foil or the copper foil with carrier on the resinsubstrate; a step of forming a circuit on the surface of the resinsubstrate with the surface-treated copper foil or the copper foil withcarrier removed therefrom; and a step of exposing the circuit formed onthe surface of the metal foil and embedded in the resin substrate byremoving the metal foil.

An embodiment of the method for producing printed wiring board accordingto the present invention using the semi-additive method, includes: astep of preparing a metal foil with a circuit formed on the surfacethereof; a step of forming a resin layer on the surface of the metalfoil so as for the circuit to be embedded; a step of laminating thesurface-treated copper foil of the present invention, via thesurface-treated layer side thereof, on the resin layer; a step ofremoving the surface-treated copper foil on the resin layer; a step offorming a circuit on the resin layer with the surface-treated copperfoil removed therefrom; and a step of exposing the circuit formed on thesurface of the metal foil and embedded in the resin layer by removingthe metal foil.

An embodiment of the method for producing a printed wiring boardaccording to the present invention, using the semi-additive method,includes: a step of forming a circuit on the surface on the ultra-thincopper layer side of a first copper foil with carrier; a step of forminga resin substrate on the surface on the ultra-thin copper layer side ofthe first copper foil with carrier so as for the circuit to be embedded;a step of preparing a second copper foil with carrier or asurface-treated copper foil, and laminating the second copper foil withcarrier or the surface-treated copper foil, via the ultra-thin copperlayer side thereof or the surface-treated layer side, respectively, onthe resin substrate; a step of peeling the carrier of the second copperfoil with carrier after laminating the second copper foil with carrieror the surface-treated copper foil on the resin substrate; a step ofobtaining the resin substrate of the present invention by removing theultra-thin copper layer or the surface-treated copper foil on the resinsubstrate after peeling the carrier of the second copper foil withcarrier; a step of forming a circuit on the surface of the resinsubstrate with the ultra-thin copper layer or the surface-treated copperfoil removed therefrom; a step of peeling the carrier of the firstcopper foil with carrier after forming the circuit on the resinsubstrate; and a step of exposing the circuit formed on the surface onthe ultra-thin copper layer side of the first copper foil with carrierand embedded in the resin substrate, by removing the ultra-thin copperlayer of the first copper foil with carrier, after peeling the carrierof the first copper foil with carrier.

An embodiment of the method for producing a printed wiring boardaccording to the present invention, using the semi-additive method,includes: a step of adopting the copper foil with carrier of the presentinvention as a first copper foil with carrier and forming a circuit onthe surface on the ultra-thin copper layer side of the first copper foilwith carrier; a step of forming a resin layer on the surface on theultra-thin copper layer side of the first copper foil with carrier so asfor the circuit to be embedded; a step of preparing a second copper foilwith carrier, and laminating the second copper foil with carrier, viathe ultra-thin copper layer side thereof of the second copper foil withcarrier, on the resin layer; a step of peeling the carrier of the secondcopper foil with carrier, a step of removing the ultra-thin copper layeron the resin layer after the peeling of the carrier of the second copperfoil with carrier; a step of forming a circuit on the surface of theresin layer with the ultra-thin copper layer removed therefrom; a stepof peeling the carrier of the first copper foil with carrier afterforming the circuit on the resin layer; and a step of exposing thecircuit formed on the surface on the ultra-thin copper layer side of thefirst copper foil with carrier and embedded in the resin layer, byremoving the ultra-thin copper layer of the first copper foil withcarrier after peeling the carrier of the first copper foil with carrier.

An embodiment of the method for producing a printed wiring boardaccording to the present invention includes: a step of preparing a metalfoil with a circuit formed on the surface thereof, a step of forming theresin substrate of the present invention on the surface of the metalfoil so as for the circuit to be embedded, a step of laminating thesurface-treated copper foil or the copper foil with carrier, via thesurface-treated layer side thereof or the ultra-thin copper layer side,respectively, on the resin substrate, and forming a circuit on the resinlayer by a semi-additive method, a subtractive method, a partly additivemethod or a modified semi-additive method; and a step of exposing thecircuit formed on the surface of the metal foil and embedded in theresin substrate by removing the metal foil.

An embodiment of the method for producing a printed wiring boardaccording to the present invention includes: a step of preparing a metalfoil with a circuit formed on the surface thereof; a step of forming aresin layer on the surface of the metal foil so as for the circuit to beembedded; a step of laminating the surface-treated copper foil of thepresent invention, via the surface-treated layer side thereof, on theresin layer, and forming a circuit on the resin layer by a subtractivemethod, a semi-additive method, a subtractive method, a partly additivemethod or a modified semi-additive method; and a step of exposing thecircuit formed on the surface of the metal foil and embedded in theresin layer by removing the metal foil.

An embodiment of the method for producing a printed wiring boardaccording to the present invention includes: a step of forming a circuiton the surface on the ultra-thin copper layer side of a first copperfoil with carrier; a step of forming the resin substrate of the presentinvention on the surface on the surface on the ultra-thin copper layerside of the first copper foil with carrier so as for the circuit to beembedded; a step of preparing a second copper foil with carrier or asurface-treated copper foil, laminating the second copper foil withcarrier or the surface-treated copper foil, via the ultra-thin copperlayer side thereof of the second copper foil with carrier or via thesurface-treated layer side thereof of the surface-treated copper foil,respectively, on the resin substrate, peeling the carrier of the secondcopper foil with carrier in the case where the second copper foil withcarrier on the resin substrate, and forming a circuit on the resinsubstrate by a semi-additive method, a subtractive method, a partlyadditive method/process or a modified semi-additive method; a step ofpeeling the carrier of the first copper foil with carrier after formingthe circuit on the resin substrate; and a step of exposing the circuitformed on the surface on the ultra-thin copper layer side of the firstcopper foil with carrier and embedded in the resin substrate by removingthe ultra-thin copper layer of the first copper foil with carrier afterpeeling the carrier of the first copper foil with carrier.

An embodiment of the method for producing a printed wiring boardaccording to the present invention includes: a step of adopting thecopper foil with carrier of the present invention as a first copper foilwith carrier and forming a circuit on the surface on the ultra-thincopper layer side of the first copper foil with carrier; a step offorming a resin layer on the surface on the ultra-thin copper layer sideof the first copper foil with carrier so as for the circuit to beembedded; a step of preparing a second copper foil with carrier,laminating the second copper foil with carrier, via the ultra-thincopper layer side thereof of the second copper foil with carrier, on theresin layer, peeling the carrier of the second copper foil with carrier,and forming a circuit on the resin layer by a semi-additive method, asubtractive method, a partly additive method or a modified semi-additivemethod; and a step of exposing the circuit formed on the surface on theultra-thin copper layer side of the first copper foil with carrier andembedded in the resin layer by removing the ultra-thin copper layer ofthe first copper foil with carrier after peeling the carrier of thefirst copper foil with carrier.

An embodiment of the method for producing a printed wiring boardaccording to the present invention includes:

-   -   a step of preparing a metal foil with a circuit formed on the        surface thereof;    -   a step of forming a resin substrate on the surface of the metal        foil so as for the circuit to be embedded;    -   a step of laminating a copper foil with carrier including a        carrier, an intermediate layer and an ultra-thin copper layer in        this order, via the surface thereof on the ultra-thin copper        layer side, on the resin substrate;    -   a step of obtaining the resin substrate of the present invention        by removing the ultra-thin copper layer on the resin substrate        after peeling the carrier of the copper foil with carrier;    -   a step of forming a circuit on the surface of the resin        substrate with the ultra-thin copper layer removed therefrom;        and    -   a step of exposing the circuit formed on the surface of the        metal foil and embedded in the resin substrate by removing the        metal foil.

An embodiment of the method for producing a printed wiring boardaccording to the present invention includes:

-   -   a step of forming a circuit on the surface on the ultra-thin        copper layer side of a copper foil with carrier including a        carrier, an intermediate layer and an ultra-thin copper layer in        this order;    -   a step of forming a resin substrate on the surface on the        ultra-thin copper layer side of the copper foil with carrier so        as for the circuit to be embedded;    -   a step of laminating the surface-treated copper foil, via the        surface-treated layer side thereof, on the resin substrate;    -   a step of obtaining the resin substrate of the present invention        by removing the surface-treated copper foil on the resin        substrate;    -   a step of forming a circuit on the surface of the resin        substrate with the surface-treated copper foil removed        therefrom;    -   a step of peeling the carrier of the copper foil with carrier        after forming the circuit on the resin substrate; and    -   a step of exposing the circuit formed on the surface on the        ultra-thin copper layer side of the copper foil with carrier and        embedded in the resin substrate by removing the ultra-thin        copper layer of the copper foil with carrier after peeling the        carrier of the copper foil with carrier.

An embodiment of the method for producing a printed wiring boardaccording to the present invention includes:

-   -   a step of preparing a metal foil with a circuit formed on the        surface thereof;    -   a step of forming the resin substrate of the present invention        on the surface of the metal foil so as for the circuit to be        embedded;    -   a step of preparing a copper foil with carrier including a        carrier, an intermediate layer and an ultra-thin copper layer in        this order, laminating the copper foil with carrier, via the        ultra-thin copper layer side thereof, on the resin substrate,        then peeling the carrier of the copper foil with carrier, and        then forming a circuit on the resin substrate; and    -   a step of exposing the circuit formed on the surface of the        metal foil and embedded in the resin substrate by removing the        metal foil.

An embodiment of the method for producing a printed wiring boardaccording to the present invention includes:

-   -   a step of forming a circuit on the surface on the ultra-thin        copper layer side of the copper foil with carrier including a        carrier, an intermediate layer and an ultra-thin copper layer in        this order;    -   a step of forming the resin substrate of the present invention        on the surface on the ultra-thin copper layer side of the copper        foil with carrier so as for the circuit to be embedded;    -   a step of laminating a surface-treated copper foil, via the        surface-treated layer side thereof, on the resin substrate, and        then forming a circuit on the resin substrate;    -   a step of peeling the carrier of the copper foil with carrier        after forming a circuit on the resin substrate; and    -   a step of exposing the circuit formed on the surface on the        ultra-thin copper layer side of the copper foil with carrier and        embedded in the resin substrate by removing the ultra-thin        copper layer of the copper foil with carrier after peeling the        carrier of the copper foil with carrier.

An embodiment of the method for producing a printed wiring boardaccording to the present invention, using the semi-additive method,includes: a step of preparing a copper foil with carrier and a resinsubstrate; a step of laminating the copper foil with carrier and theresin substrate on each other; a step of peeling the carrier of thecopper foil with carrier after laminating the copper foil with carrierand the resin substrate on each other, a step of obtaining the resinsubstrate of the present invention by completely removing the ultra-thincopper layer exposed by peeling the carrier, by a method such as etchingwith a corrosive solution such as an acid or etching with plasma; a stepof providing through-holes or/and blind vias in the resin exposed byremoving the ultra-thin copper layer by etching; a step of performingdesmear treatment in the region including the through-holes or/and blindvias; a step of providing an electroless plating layer in the regionincluding the resin and the through-holes or/and the blind vias; a stepof providing a plating resist on the electroless plating layer; a stepof exposing the plating resist, and then removing the plating resist inthe region where a circuit is to be formed; a step of providing anelectrolytic layer in the region where the plating resist is removed andthe circuit is to be formed; a step of removing the plating resist; anda step of removing the electroless plating layer in the region otherthan the region where the circuit is to be formed by flash etching orthe like.

In an embodiment, the method for producing a printed wiring board of thepresent invention includes:

a step of preparing the surface-treated copper foil of the presentinvention with a circuit formed on the surface thereof on thesurface-treated layer formed side, or the copper foil with carrier ofthe present invention, with a circuit formed on the surface thereof onthe ultra-thin copper layer side;

-   -   a step of forming a resin layer on the surface of the        surface-treated copper foil or the surface of the copper foil        with carrier so as for the circuit to be embedded;    -   a step of forming a circuit on the surface of the resin layer;        and    -   a step of exposing the circuit embedded in the resin layer by        removing the surface-treated copper foil or the copper foil with        carrier.

In an embodiment, the method for producing a printed wiring board of thepresent invention includes:

-   -   a step of preparing a metal foil with a circuit formed on the        surface thereof, or a first surface-treated copper foil being        the surface-treated copper foil of the present invention with a        circuit formed on the surface thereof on the surface-treated        layer formed side, or a metal foil with carrier with a circuit        formed on the surface thereof on the ultra-thin metal layer        side, or a first copper foil with carrier being the copper foil        with carrier of the present invention with a circuit formed on        the surface thereof on the ultra-thin copper layer side;    -   a step of forming a resin layer on the surface of the metal        foil, or the surface of the surface-treated copper foil, or the        surface of the metal foil with carrier, or the surface of the        copper foil with carrier so as for the circuit to be embedded;    -   a step of laminating the second surface-treated copper foil        being the surface-treated copper foil of the present invention,        via the surface-treated layer side thereof, on the resin layer,        or a step of laminating the second copper foil with carrier        being the copper foil with carrier of the present invention, via        the ultra-thin copper layer side thereof, on the resin layer;    -   a step of peeling the carrier of the second copper foil with        carrier, in the case where the foil laminated on the resin layer        is the second copper foil with carrier;    -   a step of removing the surface-treated copper foil on the resin        layer, or the ultra-thin copper layer remaining as a result of        peeling the carrier of the second copper foil with carrier,    -   a step of forming a circuit on the surface of the resin layer        with the surface-treated copper foil removed therefrom, or the        surface of the resin layer with the ultra-thin copper layer        removed therefrom; and    -   a step of exposing the circuit embedded in the resin layer after        forming the circuit on the resin layer by removing the metal        foil, or by removing the first surface-treated copper foil, or        by removing the ultra-thin metal layer after peeling the carrier        of the metal foil with carrier, or by removing the ultra-thin        copper layer after peeling the carrier of the first copper foil        with carrier.

In the present invention, the metal foil with carrier includes at leasta carrier and an ultra-thin metal layer in this order. As the carrier ofthe metal foil with carrier, a metal foil can be used. As the metalfoil, there can be used copper foil, copper alloy foil, nickel foil,nickel alloy foil, aluminum foil, aluminum alloy foil, iron foil, ironalloy foil, stainless steel foil, zinc foil and zinc alloy foil. Thethickness of the metal foil can be set to be 1 to 10000 μm, preferably 2to 5000 μm, preferably 10 to 1000 μm, preferably 18 to 500 μm, andpreferably 35 to 300 μm. As the carrier, a resin substrate, or an plateof an inorganic substance or an organic substance can also be used. Thethickness of the resin substrate or the plate of an inorganic substanceor an organic substance can be made the same as the above-describedthickness of the metal foil.

The carrier and the metal foil may be laminated on each other throughthe intermediary of an adhesive or a release agent, or an intermediatelayer, in a peelable manner. Alternatively, the carrier and the metalfoil may be joined to each other by welding, deposition or the like in apeelable manner. When it is difficult to peel the carrier and the metalfoil from each other, the joined portion between the carrier and themetal foil is removed by cutting or the like, and then the carrier andthe metal foil may be peeled from each other.

The ultra-thin metal layer may be formed of copper, copper alloy,nickel, nickel alloy, aluminum, aluminum alloy, iron, iron alloy,stainless steel, zinc, or zinc alloy. The thickness of the ultra-thinmetal layer is allowed to fall within the same range as the thicknessrange of the ultra-thin copper layer of the copper foil with carrier.The ultra-thin metal layer is preferably an ultra-thin copper layer fromthe viewpoint of the conductivity of the circuit formed therefrom.

In an embodiment, the method for producing a printed wiring board of thepresent invention includes:

-   -   a step of preparing the surface-treated copper foil of the        present invention, with a circuit formed on the surface thereof        on the surface-treated layer formed side, or the copper foil        with carrier of the present invention, with a circuit formed on        the surface thereof on the ultra-thin copper layer side;    -   a step of forming a resin layer on the surface of the        surface-treated copper foil or the surface of the copper foil        with carrier so as for the circuit to be embedded;    -   a step of laminating a metal foil on the resin layer, or a step        of laminating a metal foil with carrier, via the ultra-thin        metal layer side thereof, on the resin layer;    -   a step of peeling the metal foil with carrier, in the case where        the foil laminated on the resin layer is the metal foil with        carrier;    -   a step of removing the metal foil on the resin layer, or the        ultra-thin metal layer remaining as a result of peeling the        carrier of the metal foil with carrier;    -   a step of forming a circuit on the surface of the resin layer        with the metal foil removed therefrom, or the surface of the        resin layer with the ultra-thin copper layer removed therefrom;        and    -   a step of exposing the circuit embedded in the resin layer by        removing the surface-treated copper foil after forming the        circuit on the resin layer, or by removing the ultra-thin copper        layer after peeling the carrier of the copper foil with carrier.

In an embodiment, the method for producing a printed wiring board of thepresent invention includes:

-   -   a step of preparing a metal foil with a circuit formed on the        surface thereof, or a first surface-treated copper foil being        the surface-treated copper foil of the present invention with a        circuit formed on the surface thereof on the surface-treated        layer formed side, or a metal foil with carrier with a circuit        formed on the surface thereof on the ultra-thin metal layer        side, or a first copper foil with carrier being the copper foil        with carrier of the present invention with a circuit formed on        the surface thereof on the ultra-thin copper layer side;    -   a step of forming a resin layer on the surface of the metal        foil, or the surface of the surface-treated copper foil, or the        surface of the metal foil with carrier, or the surface of the        copper foil with carrier so as for the circuit to be embedded;    -   a step of laminating the second surface-treated copper foil        being the surface-treated copper foil of the present invention,        via the surface-treated layer side thereof, on the resin layer,        or a step of laminating the second copper foil with carrier        being the copper foil with carrier of the present invention, via        the ultra-thin copper layer side thereof, on the resin layer;    -   a step of peeling the carrier of the second copper foil with        carrier, in the case where the foil laminated on the resin layer        is the second copper foil with carrier;    -   a step of forming a circuit on the resin layer, by using the        surface-treated copper foil on the resin layer, or the        ultra-thin copper layer remaining as a result of peeling the        carrier of the second copper foil with carrier, by a        semi-additive method, a subtractive method, a partly additive        method or a modified semi-additive method; and    -   a step of exposing the circuit embedded in the resin layer by        removing the metal foil after forming a circuit on the resin        layer, or by removing the first surface-treated copper foil, or        by removing the ultra-thin metal layer after peeling the carrier        of the metal foil with carrier, or by removing the ultra-thin        copper layer after peeling the carrier of the first copper foil        with carrier.

In an embodiment, the method for producing a printed wiring board of thepresent invention includes:

-   -   a step of preparing the surface-treated copper foil of the        present invention with a circuit formed on the surface thereof        on the surface-treated layer formed side, or the copper foil        with carrier of the present invention with a circuit formed on        the surface thereof on the ultra-thin copper layer side;    -   a step of forming a resin layer on the surface of the        surface-treated copper foil or the surface of the copper foil        with carrier so as for the circuit to be embedded;    -   a step of laminating a metal foil on the resin layer, of a step        of laminating a metal foil with carrier, via the ultra-thin        copper layer side thereof, on the resin layer;    -   a step of peeling the carrier of the metal foil with carrier, in        the case where the foil laminated on the resin layer is the        metal foil with carrier;    -   a step of forming a circuit on the resin layer, by using the        metal foil on the resin layer, or the ultra-thin metal layer        remaining as a result of peeling the carrier of the metal foil        with carrier, by a semi-additive method, a subtractive method, a        partly additive method or a modified semi-additive method; and    -   a step of exposing the circuit embedded in the resin layer, by        removing the surface-treated copper foil after forming a circuit        on the resin layer, or by removing the ultra-thin copper layer        after peeling the carrier of the copper foil with carrier.

In an embodiment of the method for producing a printed wiring boardaccording to the present invention, using a semi-additive method,includes: a step of preparing the copper foil with carrier and theinsulating substrate according to the present invention; a step oflaminating the copper foil with carrier and the insulating substrate oneach other; a step of peeling the carrier of the copper foil withcarrier after laminating the copper foil with carrier and the insulatingsubstrate; a step of completely removing the ultra-thin copper layerexposed by peeling the carrier, by a method such as etching with acorrosive solution such as an acid or a method using plasma; a step ofproviding through-holes or/and blind vias in the resin exposed byremoving the ultra-thin copper layer by etching; a step of performingdesmear treatment in the region including the through-holes or/and blindvias; a step of providing an electroless plating layer in the regionincluding the resin and the through-holes or/and the blind vias; a stepof providing a plating resist on the electroless plating layer; a stepof exposing the plating resist, and then removing the plating resist inthe region where a circuit is to be formed; a step of providing anelectrolytic plating layer in the region where the plating resist isremoved and the circuit is to be formed; a step of removing the platingresist; and a step of removing the electroless plating layer in theregion other than the region where the circuit is to be formed by flashetching or the like.

Another embodiment of the method for producing a printed wiring boardaccording to the present invention, using a semi-additive method,includes: a step of preparing a copper foil with carrier and a resinsubstrate; a step of laminating the copper foil with carrier and theresin substrate on each other; a step of peeling the carrier of thecopper foil with carrier after laminating the copper foil with carrierand the resin substrate on each other; a step of obtaining the resinsubstrate of the present invention by completely removing the ultra-thincopper layer exposed by peeling the carrier, by a method such as etchingwith a corrosive solution such as an acid or a method using plasma; astep of providing an electroless plating layer on the surface of theresin exposed by removing the ultra-thin copper layer by etching; a stepof providing a plating resist on the electroless plating layer, a stepof exposing the plating resist, and then removing the plating resist inthe region where a circuit is to be formed; a step of providing anelectrolytic plating layer in the region where the plating resist isremoved and the circuit is to be formed; a step of removing the platingresist; and a step of removing, by flash etching or the like, theelectroless plating layer and the ultra-thin copper layer in the regionother than the region where the circuit is to be formed.

Another embodiment of the method for producing a printed wiring boardaccording to the present invention, using a semi-additive method,includes: a step of preparing the copper foil with carrier and theinsulating substrate according to the present invention; a step oflaminating the copper foil with carrier and the insulating substrate oneach other; a step of peeling the carrier of the copper foil withcarrier after laminating the copper foil with carrier and the insulatingsubstrate on each other; a step of completely removing the ultra-thincopper layer exposed by peeling the carrier, by a method such as etchingwith a corrosive solution such as an acid or etching with plasma; a stepof providing an electroless plating layer on the surface of the resinexposed by removing the ultra-thin copper layer by etching; a step ofproviding a plating resist on the electroless plating layer; a step ofexposing the plating resist, and then removing the plating resist in theregion where a circuit is to be formed; a step of providing anelectrolytic plating layer in the region where the plating resist isremoved and the circuit is to be formed; a step of removing the platingresist; and a step of removing the electroless plating layer and theultra-thin copper layer in the region other than the region where thecircuit is to be formed, by flash etching or the like.

An embodiment of the method for producing a printed wiring boardaccording to the present invention, using a modified semi-additivemethod, includes: a step of preparing a copper foil with carrier and aresin substrate; a step of laminating the copper foil with carrier andthe resin substrate on each other; a step of peeling the carrier of thecopper foil with carrier after laminating the copper foil with carrierand the resin substrate on each other; a step of providing through-holesor/and blind vias in the ultra-thin copper layer exposed by peeling thecarrier and the resin substrate; a step of obtaining the surface profileof the resin substrate of the present invention by performing desmeartreatment in the region including the through-holes or/and blind vias; astep of providing an electroless plating layer in the region includingthe through-holes or/and blind vias; a step of providing a platingresist on the surface of the ultra-thin copper layer exposed by peelingthe carrier; a step of forming a circuit by electrolytic plating afterproviding the plating resist; a step of removing the plating resist; anda step of removing, by flash etching, the ultra-thin copper layerexposed by removing the plating resist.

An embodiment of the method for producing a printed wiring boardaccording to the present invention, using a modified semi-additivemethod, includes: a step of preparing the copper foil with carrier andthe insulating substrate according to the present invention; a step oflaminating the copper foil with carrier and the insulating substrate oneach other; a step of peeling the carrier of the copper foil withcarrier after laminating the copper foil with carrier and the insulatingsubstrate on each other; a step of providing through-holes or/and blindvias in the ultra-thin copper layer exposed by peeling the carrier andthe insulating substrate; a step of performing a desmear treatment inthe region including the through-holes or/and blind vias; a step ofproviding an electroless plating layer in the region including thethrough-holes or/and blind vias; a step of providing a plating resist onthe surface of the ultra-thin copper layer exposed by peeling thecarrier; a step of forming a circuit by electrolytic plating afterproviding the plating resist; a step of removing the plating resist; anda step of removing the ultra-thin copper layer exposed by removing theplating resist, by flash etching.

Another embodiment of the method for producing a printed wiring boardaccording to the present invention, using a modified semi-additivemethod, includes: a step of preparing a copper foil with carrier and aresin substrate; a step of laminating the copper foil with carrier andthe resin substrate on each other; a step of peeling the carrier of thecopper foil with carrier after laminating the copper foil with carrierand the resin substrate on each other; a step of providing a platingresist on the ultra-thin copper layer exposed by peeling the carrier; astep of exposing the plating resist, and then removing the platingresist in the region where a circuit is to be formed; a step ofproviding an electrolytic plating layer in the region where the platingresist is removed and the circuit is to be formed; a step of removingthe plating resist; and a step of obtaining the surface profile of theresin substrate of the present invention by removing, by flash etchingor the like, the electroless plating layer and the ultra-thin copperlayer in the region other than the region where the circuit is to beformed.

Another embodiment of the method for producing a printed wiring boardaccording to the present invention, using a modified semi-additivemethod, includes: a step of preparing the copper foil with carrier andthe insulating substrate according to the present invention; a step oflaminating the copper foil with carrier and the insulating substrate oneach other; a step of peeling the carrier of the copper foil withcarrier after laminating the copper foil with carrier and the insulatingsubstrate on each other; a step of providing a plating resist on theultra-thin copper layer exposed by peeling the carrier; a step ofexposing the plating resist, and then removing the plating resist in theregion where a circuit is to be formed; a step of providing anelectrolytic plating layer in the region where the plating resist isremoved and the circuit is to be formed; and a step of removing, byflash etching or the like, the electroless plating layer and theultra-thin copper layer in the region other than the region where thecircuit is to be formed.

An embodiment of the method for producing a printed wiring boardaccording to the present invention, using a partly additive method,includes: a step of preparing a copper foil with carrier and a resinsubstrate; a step of laminating the copper foil with carrier and theresin substrate on each other; a step of peeling the carrier of thecopper foil with carrier after laminating the copper foil with carrierand the resin substrate on each other; a step of providing through-holesor/and blind vias in the ultra-thin copper layer exposed by peeling thecarrier and the resin substrate; a step of obtaining the surface profileof the resin substrate of the present invention by performing a desmeartreatment in the region including the through-holes or/and blind vias; astep of imparting catalyst nuclei to the region including thethrough-holes or/and the blind vias; a step of providing an etchingresist on the surface of the ultra-thin copper layer exposed by peelingthe carrier; a step of forming a circuit pattern by exposing the etchingresist; a step of forming a circuit by removing the ultra-thin copperlayer and the catalyst nuclei by a method such as etching with acorrosive solution such as an acid or by etching with plasma; a step ofremoving the etching resist; a step of providing a solder resist or aplating resist on the surface of the resin substrate exposed by removingthe ultra-thin copper layer and the catalyst nuclei by a method such asetching with a corrosive solution such as an acid or etching withplasma; and a step of providing an electroless plating layer in theregion where neither a solder resist nor a plating resist is provided.

An embodiment of the method for producing a printed wiring boardaccording to the present invention, using a partly additive method,includes: a step of preparing the copper foil with carrier and theinsulating substrate according to the present invention; a step oflaminating the copper foil with carrier and the insulating substrate oneach other; a step of peeling the carrier of the copper foil withcarrier after laminating the copper foil with carrier and the insulatingsubstrate on each other; a step of providing through-holes or/and blindvias in the ultra-thin copper layer exposed by peeling the carrier andthe insulating substrate; a step of performing a desmear treatment inthe region including the through-holes or/and the blind vias; a step ofimparting catalyst nuclei to the region including the through-holesor/and the blind vias; a step of providing an etching resist on thesurface of the ultra-thin copper layer exposed by peeling the carrier: astep of forming a circuit pattern by exposing the etching resist; a stepof forming a circuit by removing the ultra-thin copper layer and thecatalyst nuclei by a method such as etching with a corrosive solutionsuch as an acid or by etching with plasma; a step of removing theetching resist; a step of providing a solder resist or a plating resiston the surface of the insulating substrate exposed by removing theultra-thin copper layer and the catalyst nuclei by a method such asetching with a corrosive solution such as an acid or etching withplasma; and a step of providing an electroless plating layer in theregion where neither a solder resist nor a plating resist is provided.

An embodiment of the method for producing a printed wiring boardaccording to the present invention, using a subtractive method,includes: a step of preparing a copper foil with carrier and a resinsubstrate; a step of laminating the copper foil with carrier and theresin substrate on each other; a step of peeling the carrier of thecopper foil with carrier after laminating the copper foil with carrierand the resin substrate; a step of providing through-holes or/and blindvias in the ultra-thin copper layer exposed by peeling the carrier andthe resin substrate; a step of obtaining the surface profile of theresin substrate of the present invention by performing a desmeartreatment in the region including the through-holes or/and the blindvias; a step of providing an electroless plating layer in the regionincluding the through-holes or/and the blind vias; a step of providingan electrolytic plating layer on the surface of the electroless platinglayer; a step of providing an etching resist on the surface of theelectrolytic plating layer or/and the surface of the ultra-thin copperlayer; a step of forming a circuit pattern by exposing the etchingresist; a step of forming a circuit by removing the ultra-thin copperlayer, and the electroless plating layer and the electrolytic platinglayer, by a method such as etching with a corrosive solution such as anacid or etching with plasma; and a step of removing the etching resist.

An embodiment of the method for producing a printed wiring boardaccording to the present invention, using a subtractive method,includes: a step of preparing the copper foil with carrier and theinsulating substrate according to the present invention; a step oflaminating the copper foil with carrier and the insulating substrate oneach other; a step of peeling the carrier of the copper foil withcarrier after laminating the copper foil with carrier and the insulatingsubstrate on each other; a step of providing through-holes or/and blindvias in the ultra-thin copper layer exposed by peeling the carrier andthe insulating substrate; a step of performing a desmear treatment inthe region including the through-holes or/and the blind vias; a step ofproviding an electroless plating layer in the region including thethrough-holes or/and the blind vias; a step of providing an electrolyticplating layer on the surface of the electroless plating layer; a step ofproviding an etching resist on the surface of the electrolytic platinglayer or/and the surface of the ultra-thin copper layer; a step offorming a circuit pattern by exposing the etching resist; a step offorming a circuit by removing the ultra-thin copper layer, and theelectroless plating layer and the electrolytic plating layer, by amethod such as etching with a corrosive solution such as an acid oretching with plasma; and a step of removing the etching resist.

Another embodiment of the method for producing a printed wiring boardaccording to the present invention, using a subtractive method,includes: a step of preparing a copper foil with carrier and a resinsubstrate; a step of laminating the copper foil with carrier and theresin substrate on each other; a step of peeling the carrier of thecopper foil with carrier after laminating the copper foil with carrierand the resin substrate on each other, a step of providing through-holesor/and blind vias in the ultra-thin copper layer exposed by peeling thecarrier and the resin substrate; a step of obtaining the surface profileof the resin substrate of the present invention by performing a desmeartreatment in the region including the through-holes or/and the blindvias; a step of providing an electroless plating layer in the regionincluding the through-holes or/and the blind vias; a step of forming amask on the surface of the electroless plating layer; a step ofproviding an electrolytic plating layer on the surface of theelectroless plating layer with no mask formed thereon; a step ofproviding an etching resist on the surface of the electrolytic platinglayer or/and the surface of the ultra-thin copper layer; a step offorming a circuit pattern by exposing the etching resist; a step offorming a circuit by removing the ultra-thin copper layer and theelectroless plating layer by a method such as etching with a corrosivesolution such as an acid or etching with plasma; and a step of removingthe etching resist.

Another embodiment of the method for producing a printed wiring boardaccording to the present invention, using a subtractive method,includes: a step of preparing the copper foil with carrier and theinsulating substrate according to the present invention; a step oflaminating the copper foil with carrier and the insulating substrate oneach other; a step of peeling the carrier of the copper foil withcarrier after laminating the copper foil with carrier and the insulatingsubstrate on each other; a step of providing through-holes or/and blindvias in the ultra-thin copper layer exposed by peeling the carrier andthe insulating substrate; a step of performing a desmear treatment inthe region including the through-holes or/and the blind vias; a step ofproviding an electroless plating layer in the region including thethrough-holes or/and the blind vias; a step of forming a mask on thesurface of the electroless plating layer; a step of providing anelectrolytic plating layer on the surface of the electroless platinglayer with no mask formed thereon; a step of providing an etching resiston the surface of the electrolytic plating layer or/and the surface ofthe ultra-thin copper layer; a step of forming a circuit pattern byexposing the etching resist; a step of forming a circuit by removing theultra-thin copper layer and the electroless plating layer by a methodsuch as etching with a corrosive solution such as an acid or etchingwith plasma; and a step of removing the etching resist.

The step of providing through-holes or/and blind vias, and thesubsequent desmear step may be omitted.

Here, a specific example of the method for producing a printed wiringboard, using the copper foil with carrier of the present invention isdescribed in detail.

-   -   Step 1: First, a copper foil with carrier (first layer) having        an ultra-thin copper layer with a roughening-treated layer on        the surface thereof is prepared.    -   Step 2: Next, a resist is applied on the roughening-treated        layer of the ultra-thin copper layer, exposure and development        are performed to etch the resist into a predetermined shape.    -   Step 3: Next, after forming a plating for a circuit, the resist        is removed, and thus a circuit plating having a predetermined        shape is formed.    -   Step 4: Next, a resin layer is laminated on the ultra-thin        copper layer by providing embedding resin so as for the circuit        plating to be covered (so as for the circuit plating to be        embedded), and successively another copper foil with carrier        (second layer) is made to adhere to the ultra-thin copper layer        side.    -   Step 5: Next, from the copper foil with carrier as the second        layer, the carrier is peeled. Alternatively, as the second        layer, a copper foil having no carrier may also be used.    -   Step 6: Next, laser drilling is performed at the predetermined        positions of the ultra-thin copper layer as the second layer, or        the copper foil and the resin layer, and thus the circuit        plating is exposed to form a blind via.    -   Step 7: Next, copper is implanted into the blind via to form a        via fill.    -   Step 8: Next, on the via fill, a circuit plating is formed in        the same manner as in above-described Steps 2 and 3.    -   Step 9: Next, from the copper foil with carrier as the first        layer, the carrier is peeled.    -   Step 10: Next, by flash etching, the ultra-thin copper layers on        both surfaces (in the case where as the second layer, a copper        foil is provided, the copper foil is removed) are removed, to        expose the surface of the circuit plating in the resin layer.    -   Step 11: Next, a bump is formed on the circuit plating in the        resin layer, and a copper pillar is formed on the solder        concerned. In this way, a printed wiring board using the copper        foil with carrier of the present invention is prepared.

As the added copper foil with carrier (second layer), the copper foilwith carrier of the present invention may be used, a conventional copperfoil with carrier may also be used, and moreover, a common copper foilmay also be used. In addition, on the circuit on the second layer inStep 8, a layer of a circuit or a plurality of layers of circuits may beformed, and the formation of these circuits may also be performed by asemi-additive method, a subtractive method, a partly additive method ora modified semi-additive method.

According to such a method for producing a printed wiring board asdescribed above, because of the constitution allowing the circuitplating to be embedded in the resin layer, during removing theultra-thin copper layer by flash etching as in, for example, the step10, the circuit plating is protected by the resin layer, the shape ofthe circuit plating is maintained, and accordingly the formation of afine circuit is facilitated. In addition, because the circuit plating isprotected by the resin layer, the migration resistance is improved andthe conduction of the circuit wiring is suppressed satisfactorily.Accordingly, the formation of a fine circuit is facilitated. As shown inthe step 10 and the step 11, when the ultra-thin copper layer is removedby flash etching, the exposed surface of the circuit plating takes ashape recessed from the resin layer, and hence the formation of a bumpon the circuit plating concerned, and moreover the formation of a copperpillar thereon are facilitated to improve the production efficiency.

As the embedding resin (resin, heretofore known resins and prepregs canbe used. For example, there can be used BT (bismaleimide triazine)resin, a prepreg being a glass cloth impregnated with BT resin, and theABF film and ABF manufactured by Ajinomoto Fine-Techno Co., Ltd. As theembedding resin (resin), the resin layer and/or the resin and/or theprepreg described in the present description can also be used.

The copper foil with carrier used as the first layer may have asubstrate or a resin layer on the surface of the copper foil withcarrier concerned. Because of having the substrate concerned of theresin layer concerned, the copper foil with carrier used as the firstlayer is supported and hardly undergoes wrinkles to offer an advantagethat the productivity is improved. As the substrate or the resin layer,any substrate or any resin layer that has an effect to support thecopper foil with carrier used as the first layer can be used. Forexample, as the substrate or the resin layer, the carriers, prepregs,and resin layers described in the description of the presentapplication, and heretofore known carriers, prepregs, resin layers,metal plates, metal foils, plates of inorganic compounds, foils ofinorganic compounds, plates of organic compounds and foils of organiccompounds can be used.

In addition, by mounting electronic components and the like on theprinted wiring board, a printed circuit board is completed. In thepresent invention, the “printed wiring board” is defined to include sucha printed wiring board with electronic components mounted thereon, aprinted circuit board, and a printed substrate.

Additionally, electronic devices may also be fabricated by using theprinted wiring board concerned, electronic devices may also befabricated by using the printed wiring board concerned with electroniccomponents mounted thereon, or electronic devices may also be fabricatedby using the printed substrate concerned with electronic componentsmounted thereon.

EXAMPLES

Hereinafter, Examples of the present invention are described; theseExamples are presented for the purpose of better understanding of thepresent invention and the advantages thereof, and are not intended tolimit the present invention.

In present Example, as described below, the surface profile of the resinsubstrate formed by using a copper foil and the surface profile of theresin substrate formed by using a chemical solution were produced.

1. Formation of Surface Profile of Resin Substrate Using Copper Foil

FIG. 2 illustrates a production flow of samples for obtaining the dataof Examples and Comparative Examples.

As Examples A1 to A11 and Comparative Examples A1 to A4, and as thecopper foils for producing the substrate surface profiles of Examples B1to B8, Examples B10 to B12 and Comparative Examples B1 to B4, thefollowing copper foil bulk layers (raw foils) were prepared.

Common Electrolytic Raw Foil

A copper sulfate electrolyte having a copper concentration of 80 to 120g/L, a sulfuric acid concentration of 80 to 120 g/L, a chloride ionconcentration of 30 to 100 ppm and a glue concentration of 1 to 5 ppm,and a electrolyte temperature of 57 to 62° C. was used as anelectrolytic copper plating bath, a linear speed of the electrolyteflowing between the anode and the cathode (a metal drum forelectrodeposition for copper foil) was set at 1.5 to 2.5 m/sec, and acurrent density was set at 70 A/dm², and thus, a common electrolytic rawfoil having a thickness of 12 μm (thickness in terms of weight per unitarea: 95 g/m²) was produced.

Double-Sided Flat Electrolytic Raw Foils

A copper sulfate electrolyte having a copper concentration of 80 to 120g/L, a sulfuric acid concentration of 80 to 120 g/L, a chloride ionconcentration of 30 to 100 ppm, a leveling agent 1 (bis(3-sulfopropyl)disulfide) concentration of 10 to 30 ppm and a leveling agent 2 (anamine compound) concentration of 10 to 30 ppm and a electrolytetemperature of 57 to 62° C. was used as an electrolytic copper platingbath, a linear speed of the electrolyte flowing between the anode andthe cathode (a metal drum for electrodeposition for copper foil) was setat 1.5 to 2.5 m/sec, and a current density was set at 70 A/dm², andthus, a double flat sided electrolytic raw foil having a thickness of 12μm (thickness in terms of weight per unit area: 95 g/m²) was produced.As the amine compound, an amine compound represented by the followingchemical formula was used.

(wherein, in the chemical formula, R₁ and R₂ are each a group selectedfrom the group consisting of a hydroxyalkyl group, an ether group, anaryl group, an aromatic-substituted alkyl group, an unsaturatedhydrocarbon group and an alkyl group.)

Ultra-Thin Raw Copper Foil with Carrier

Under the above-described production conditions of the double flat sidedelectrolytic raw foil, a double flat sided electrolytic raw foil havinga thickness of 18 μm was produced. By using this as a copper foilcarrier, a release layer and an ultra-thin copper layer were formed bythe following methods, and thus ultra-thin copper foils with carrierhaving thicknesses of 1.5, 2, 3 and 5 μm were obtained.

(1) Ni Layer (Release Layer: Base Plating 1)

On the S surface of the copper foil carrier, a Ni layer having adeposition amount of 1000 μg/dm² was formed by performing electroplatingwith a roll-to-roll type continuous plating line under the followingconditions. The specific plating conditions are shown below.

Nickel sulfate: 270 to 280 g/L

Nickel chloride: 35 to 45 g/L

Nickel acetate: 10 to 20 g/L

Boric acid: 30 to 40 g/L

Gloss agent: Saccharin, butynediol and the like

Sodium dodecyl sulfate: 55 to 75 ppm

pH: 4 to 6

Bath temperature: 55 to 65° C.

Current density: 10 A/dm²

(2) Cr Layer (Release Layer: Base Plating 2)

Next, after the surface of the Ni layer formed in (1) was washed withwater and washed with an acid, successively on the roll-to-roll typecontinuous plating line, on the Ni layer, a Cr layer having a depositionamount of 11 μg/dm² was attached by performing an electrolytic chromatetreatment under the following conditions.

Potassium bichromate: 1 to 10 g/L, zinc: 0 g/L

pH: 7 to 10

Solution temperature: 40 to 60° C.

Current density: 2 A/dm²

(3) Ultra-Thin Copper Layer

Next, after the surface of the Cr layer formed in (2) was washed withwater and washed with an acid, successively on the roll-to-roll typecontinuous plating line, on the Cr layer, ultra-thin copper layershaving thicknesses of 1.5, 2, 3 and 5 μm were formed by performingelectroplating under the following conditions, and thus ultra-thincopper foils with carrier were produced.

-   -   Copper concentration: 80 to 120 g/L    -   Sulfuric acid concentration: 80 to 120 g/L    -   Chloride ion concentration: 30 to 100 ppm    -   Leveling agent 1 (bis(3-sulfopropyl) disulfide): 10 to 30 ppm    -   Leveling agent 2 (amine compound): 10 to 30 ppm

As the leveling agent 2, the following amine compound was used. As theamine compound, an amine compound represented by the following chemicalformula was used.

(wherein, in the chemical formula, R₁ and R₂ are each a group selectedfrom the group consisting of a hydroxyalkyl group, an ether group, anaryl group, an aromatic-substituted alkyl group, an unsaturatedhydrocarbon group and an alkyl group.)

-   -   Electrolyte temperature: 50 to 80° C.    -   Current density: 100 A/dm²

Next, on the M surface (matte surface), namely, the surface, on the sideadhering to the resin substrate, of the raw foil resin substrate or theS surface (shiny surface) of the raw foil, the surface treatments,namely, a roughening treatment, a barrier treatment, a rust-preventingtreatment and an application of a silane coupling agent were applied inthis order. The treatment conditions are shown below.

[Roughening Treatment]

Spherical Roughening (Ordinary):

The M surface or the S surface of each of the above-described variousraw foils were subjected to the roughening treatment under the followingconditions.

(Electrolyte Composition)

-   -   Cu: 20 to 30 g/L (added as copper sulfate pentahydrate, the same        applies hereinafter)    -   H₂SO₄: 80 to 120 g/L    -   Arsenic: 1.0 to 2.0 g/L

(Electrolyte Temperature)

-   -   35 to 40° C.

(Current Condition)

-   -   Current density: 70 A/dm²

On the M surface of each of the various copper foils and the surface ofeach of the ultra-thin copper foils with carrier, subjected to theroughening treatment under the above-described conditions, a coveringplating was performed in a copper electrolyte bath composed of sulfuricacid and copper sulfate, in order to prevent the dropout of roughenedparticles and improving the peel strength. The covering platingconditions are shown below.

(Electrolyte Composition)

-   -   Cu: 40 to 50 g/L    -   H₂SO₄: 80 to 120 g/L

(Electrolyte Temperature)

-   -   43 to 47° C.

(Current Condition)

-   -   Current density: 29 A/dm²

Fine roughening (1):

The M surface of each of the above-described various raw foil and thesurface of each of the above-described various ultra-thin raw copperfoils with carrier were subjected to a roughening treatment under thefollowing conditions.

(Electrolyte Composition)

-   -   Cu concentration: 10 to 20 g/L    -   H₂SO₄ concentration: 80 to 120 g/L    -   Tungsten concentration: 1 to 10 mg/L (added as sodium tungstate        dihydrate)    -   Sodium dodecyl sulfate concentration: 1 to 10 mg/L

(Electrolyte Temperature)

-   -   35 to 45° C.

(Current Conditions)

In order to obtain the predetermined hole shapes, current was impartedin four stages. The current densities were set as follows.

-   -   First stage: 30 A/dm²    -   Second stage: 10 A/dm²    -   Third stage: 30 A/dm²    -   Fourth stage: 10 A/dm²

On the M surface of each of the various copper foils and the surface ofeach of the ultra-thin copper foils with carrier, subjected to theroughening treatment under the above-described conditions, a coveringplating was performed in a copper electrolyte bath composed of sulfuricacid and copper sulfate, in order to prevent the dropout of roughenedparticles and improving the peel strength. The covering platingconditions are described below.

(Electrolyte Composition)

-   -   Cu: 40 to 50 g/L    -   H₂SO₄: 80 to 120 g/L

(Electrolyte Temperature)

-   -   43 to 47° C.

(Current Condition)

-   -   Current density: 41 A/dm²

Fine Roughening (2):

The surface of each of the above-described ultra-thin raw copper foilswith carrier were subjected to a roughening treatment under thefollowing conditions.

(Electrolyte Composition)

-   -   Cu concentration: 10 to 20 g/L    -   H₂SO₄ concentration: 80 to 120 g/L    -   Tungsten concentration: 1 to 10 mg/L (added as sodium tungstate        dihydrate)    -   Sodium dodecyl sulfate concentration: 1 to 10 mg/L

(Electrolyte Temperature)

-   -   35 to 45° C.

(Current Conditions)

In order to obtain the predetermined hole shapes, a two-stage processwas applied. The current densities were set as follows.

-   -   First stage: 50 A/dm²    -   Second stage: 10 A/dm²

On the M surface of each of the various copper foils and the surface ofeach of the ultra-thin copper foils with carrier, subjected to theroughening treatment under the above-described conditions, a coveringplating was performed in a copper electrolyte bath composed of sulfuricacid and copper sulfate, in order to prevent the dropout of roughenedparticles and improving the peel strength. The covering platingconditions are described below.

(Electrolyte Composition)

-   -   Cu: 40 to 50 g/L    -   H₂SO₄: 80 to 120 g/L

(Electrolyte Temperature)

-   -   43 to 47° C.

(Current Condition)

-   -   Current density: 41 A/dm²

Fine Roughening (3):

The M surface of each of the above-described double flat sidedelectrolytic raw foils, and the surface of each of the above-describedvarious ultra-thin raw copper foils with carrier were subjected to aroughening treatment under the following conditions.

(Electrolyte Composition)

-   -   Cu: 10 to 20 g/L    -   Co: 1 to 10 g/L    -   Ni: 1 to 10 g/L    -   pH: 1 to 4

(Electrolyte Temperature)

-   -   40 to 50° C.

(Current Condition)

-   -   Current density: 25 A/dm²

(Immersion Time in Plating Solution after Completion of Plating)

In order to obtain a predetermined hole shape, the immersion time wasset within 5 seconds.

The M surface of each of the double flat sided copper foils and thesurface of each of the ultra-thin copper foils with carrier, subjectedto the roughening treatment under the above-described conditions, weresubjected to a covering Co—Ni plating. The covering plating conditionsare described below.

(Electrolyte Composition)

-   -   Co: 1 to 30 g/L    -   Ni: 1 to 30 g/L    -   pH: 1.0 to 3.5

(Electrolyte Temperature)

-   -   30 to 80° C.

(Current Condition)

-   -   Current density: 5.0 A/dm²

Fine Roughening (4):

The surface of each of the above-described ultra-thin raw copper foilswith carrier was subjected to a roughening treatment to form primaryparticles and secondary particles under the following conditions.

Formation of primary particles:

(Electrolyte Composition)

-   -   Cu concentration: 10 to 20 g/L    -   H₂SO₄ concentration: 80 to 120 g/L    -   Tungsten concentration: 1 to 10 mg/L (added as sodium tungstate        dihydrate)    -   Sodium dodecyl sulfate concentration: 1 to 10 mg/L

(Electrolyte Temperature)

-   -   35 to 45° C.

(Current Conditions)

In order to obtain the predetermined hole shapes, a two-stage processwas applied. The current densities were set as follows.

-   -   First stage: 50 A/dm²    -   Second stage: 10 A/dm²

On the surface of each of the ultra-thin copper foils with carrier,subjected to the formation of primary roughened particles under theabove-described conditions, a covering plating was performed in a copperelectrolyte bath composed of sulfuric acid and copper sulfate, in orderto prevent the dropout of the primary roughened particles and improvingthe peel strength. The covering plating conditions are described below.

(Electrolyte Composition)

-   -   Cu: 40 to 50 g/L    -   H₂SO₄: 80 to 120 g/L

(Electrolyte Temperature)

-   -   43 to 47° C.

(Current Condition)

-   -   Current density: 41 A/dm²

Formation of Secondary Particles:

Next, a roughening treatment to form secondary roughened particles onthe primary roughened particles of each of the ultra-thin copper foilswith carrier was performed.

(Electrolyte Composition)

-   -   Cu: 10 to 20 g/L    -   Co: 1 to 10 g/L    -   Ni: 1 to 10 g/L    -   pH: 1 to 4

(Electrolyte Temperature)

-   -   40 to 50° C.

(Current Condition)

-   -   Current density: 25 A/dm²

(Immersion Time in Plating Solution after Completion of Plating)

In order to obtain a predetermined hole shape, the immersion time wasset within 5 seconds.

The surface of each of the ultra-thin copper foils with carrier,subjected to the secondary particle roughening treatment under theabove-described conditions, were subjected to a covering Co—Ni plating.The covering plating conditions are described below.

(Electrolyte Composition)

-   -   Co: 1 to 30 g/L    -   Ni: 1 to 30 g/L    -   pH: 1.0 to 3.5

(Electrolyte Temperature)

-   -   30 to 80° C.

(Current Condition)

-   -   Current density: 5.0 A/dm²

Fine Roughening (5):

A roughening treatment to form the primary particles and the secondaryparticles on the surface of each of the above-described ultra-thin rawcopper foils with carrier was performed.

Formation of Primary Particles:

(Electrolyte Composition)

-   -   Cu concentration: 10 to 20 g/L    -   H₂SO₄ concentration: 80 to 120 g/L    -   Tungsten concentration: 1 to 10 mg/L (added as sodium tungstate        dihydrate)    -   Sodium dodecyl sulfate concentration: 1 to 10 mg/L

(Electrolyte Temperature)

-   -   35 to 45° C.

(Current Conditions)

In order to obtain the predetermined hole shapes, a two-stage processwas applied. The current densities were set as follows.

-   -   First stage: 20 A/dm²    -   Second stage: 10 A/dm²

On the surface of each of the ultra-thin copper foils with carrier,subjected to the formation of primary roughened particles under theabove-described conditions, a covering plating was performed in a copperelectrolyte bath composed of sulfuric acid and copper sulfate, in orderto prevent the dropout of the primary roughened particles and improvingthe peel strength. The covering plating conditions are described below.

(Electrolyte Composition)

-   -   Cu: 40 to 50 g/L    -   H₂SO₄: 80 to 120 g/L

(Electrolyte Temperature)

-   -   43 to 47° C.

(Current Condition)

-   -   Current density: 41 A/dm²

Formation of Secondary Particles:

Next, a roughening treatment to form secondary roughened particles onthe primary roughened particles of each of the ultra-thin copper foilswith carrier was performed.

(Electrolyte Composition)

-   -   Cu: 10 to 20 g/L    -   Co: 1 to 10 g/L    -   Ni: 1 to 10 g/L    -   pH: 1 to 4

(Electrolyte Temperature)

-   -   40 to 50° C.

(Current Condition)

-   -   Current density: 25 A/dm²

(Immersion Time in Plating Solution after Completion of Plating)

In order to obtain a predetermined hole shape, the immersion time wasset to be 15 to 20 seconds.

The surface of each of the ultra-thin copper foils with carrier,subjected to the secondary particle roughening treatment under theabove-described conditions, were subjected to a covering Co—Ni plating.The covering plating conditions are described below.

(Electrolyte Composition)

-   -   Co: 1 to 30 g/L    -   Ni: 1 to 30 g/L    -   pH: 1.0 to 3.5

(Electrolyte Temperature)

-   -   30 to 80° C.

(Current Condition)

-   -   Current density: 5.0 A/dm²

Fine Roughening (6):

The surface of each of the above-described ultra-thin raw copper foilwith carrier was subjected to a roughening treatment under the followingconditions.

(Electrolyte Composition)

-   -   Cu concentration: 10 to 20 g/L    -   H₂SO₄ concentration: 80 to 120 g/L    -   Tungsten concentration: 1 to 10 mg/L (added as sodium tungstate        dihydrate)    -   Sodium dodecyl sulfate concentration: 1 to 10 mg/L

(Electrolyte Temperature)

-   -   35 to 45° C.

(Current Conditions)

In order to obtain the predetermined hole shapes, a four-stage processwas applied. The current densities were set as follows.

-   -   First stage: 50 A/dm²    -   Second stage: 10 A/dm²    -   Third stage: 50 A/dm²    -   Fourth stage: 10 A/dm²

On the M surface of each of the various copper foils and the surface ofeach of the ultra-thin copper foils with carrier, subjected to theroughening treatment under the above-described conditions, a coveringplating was performed in a copper electrolyte bath composed of sulfuricacid and copper sulfate, in order to prevent the dropout of roughenedparticles and improving the peel strength. The covering platingconditions are described below.

(Electrolyte Composition)

-   -   Cu: 40 to 50 g/L    -   H₂SO₄: 80 to 120 g/L

(Electrolyte Temperature)

-   -   43 to 47° C.

(Current Condition)

-   -   Current density: 41 A/dm²    -   Fine Roughening (7):

A roughening treatment to form the primary particles and the secondaryparticles on the surface of each of the above-described ultra-thin rawcopper foils with carrier was performed.

Formation of Primary Particles:

(Electrolyte Composition)

-   -   Cu concentration: 10 to 20 g/L    -   H₂SO₄ concentration: 80 to 120 g/L    -   Tungsten concentration: 1 to 10 mg/L (added as sodium tungstate        dihydrate)    -   Sodium dodecyl sulfate concentration: 1 to 10 mg/L

(Electrolyte Temperature)

-   -   35 to 45° C.

(Current Conditions)

In order to obtain the predetermined hole shapes, a three-stage processwas applied. The current densities were set as follows.

-   -   First stage: 25 A/dm²    -   Second stage: 10 A/dm²    -   Third stage: 5 A/dm²

On the surface of each of the ultra-thin copper foils with carrier,subjected to the formation of primary roughened particles under theabove-described conditions, a covering plating was performed in a copperelectrolyte bath composed of sulfuric acid and copper sulfate, in orderto prevent the dropout of the primary roughened particles and improvingthe peel strength. The covering plating conditions are described below.

(Electrolyte Composition)

-   -   Cu: 40 to 50 g/L    -   H₂SO₄: 80 to 120 g/L

(Electrolyte Temperature)

-   -   43 to 47° C.

(Current Condition)

-   -   Current density: 41 A/dm²

Formation of Secondary Particles:

Next, a roughening treatment to form secondary roughened particles onthe primary roughened particles of each of the ultra-thin copper foilswith carrier was performed.

(Electrolyte Composition)

-   -   Cu: 10 to 20 g/L    -   Co: 1 to 10 g/L    -   Ni: 1 to 10 g/L    -   pH: 1 to 4

(Electrolyte Temperature)

-   -   40 to 50° C.

(Current Condition)

-   -   Current density: 25 A/dm²

(Immersion Time in Plating Solution after Completion of Plating)

In order to obtain a predetermined hole shape, the immersion time wasset to be 5 to 10 seconds.

The surface of each of the ultra-thin copper foils with carrier,subjected to the secondary particle roughening treatment under theabove-described conditions, were subjected to a covering Co—Ni plating.The covering plating conditions are described below.

(Electrolyte Composition)

-   -   Co: 1 to 30 g/L    -   Ni: 1 to 30 g/L    -   pH: 1.0 to 3.5

(Electrolyte Temperature)

-   -   30 to 80° C.

(Current Condition)

-   -   Current density: 5.0 A/dm²

[Barrier (Heat Resistance) Treatment]

A barrier (heat resistance) treatment was performed under the followingconditions, to form a brass plating layer or a zinc-nickel alloy platinglayer.

Formation conditions of barrier layers (brass plating) of Example A6,comparative Examples A2 and A3, Example B6, and Comparative Examples B2and B3:

By using a brass plating bath having a copper concentration of 50 to 80g/L, a zinc concentration of 2 to 10 g/L, a sodium hydroxideconcentration of 50 to 80 g/L, a sodium cyanate concentration of 5 to 30g/L, and being set at a temperature of 60 to 90° C., a plating electricquantity of 30 As/dm² was imparted to the M surface having aroughening-treated layer formed thereon, at a current density of 5 to 10A/dm² (multistage treatment).

Formation conditions of barrier layers (zinc-nickel plating) of ExampleA3, Comparative Example A1, Example B3 and Comparative Example B1:

By using a plating bath containing, as added therein, Ni: 10 g/L to 30g/L, Zn: 1 g/L to 15 g/L, sulfuric acid (H₂SO₄): 1 g/L to 12 g/L, andchloride ion: 0 g/L to 5 g/L, a plating electric quantity of 5.5 As/dm²was imparted to the M surface having a roughening-treated layer formedthereon, at a current density of 1.3 A/dm².

[Rust-Preventing Treatment]

A rust-preventing treatment (chromate treatment) was performed under thefollowing conditions to form a rust-preventing layer.

(Chromate conditions) In a chromate bath containing CrO₃: 2.5 g/L, Zn:0.7 g/L, and Na₂SO₄: 10 g/L, having a pH 4.8, and being set at 54° C.,an electric quantity of 0.7 As/dm² was added. Moreover, immediatelyafter the completion of the rust-preventing treatment in the chromatebath, by using a liquid shower pipe, the whole roughening-treatedsurface was subjected to a showering by using the same chromate bath.

[Application of Silane Coupling Agent]

A silane coupling agent application treatment was performed by sprayinga solution containing 0.2 to 2% of an alkoxysilane and having a pH of 7to 8 to the roughening-treated surface of a copper foil.

Moreover, in each of Examples A8 and B8, after the rust-preventingtreatment and the application of a silane coupling agent, a resin layerwas formed under the following conditions.

(Example of Resin Synthesis)

In a 2-liter three-necked flask equipped with a stainless steelanchor-type stirring rod, a nitrogen introduction tube and a refluxcondenser equipped with a bulb condenser equipped on the top of a trapwith stopcock, 117.68 g (400 mmol) of 3,4,3′,4′-biphenyltetracarboxylicacid dihydrate, 87.7 g (300 mmol) of 1,3-bis(3-aminophenoxy)benzene, 4.0g (40 mmol) of γ-valerolactone, 4.8 g (60 mmol) of pyridine, 300 g ofN-methyl-2-pyrrolidone (hereinafter denoted as NMP), and 20 g of toluenewere added, the resulting mixture was heated at 180° C. for 1 hour andthen cooled to around room temperature, subsequently 29.42 g (100 mmol)of 3,4,3′,4′-biphenyltetracarboxylic acid dihydrate, 82.12 g (200 mmol)of 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 200 g of NMP and 40 g oftoluene were added to the mixture, the resulting mixture was mixed atroom temperature for 1 hour and then heated at 180° C. for 3 hours, andthus a block copolymerized polyimide having a solid content of 38%. Thisblock copolymerized polyimide had a ratio between the following generalformulas (1) and (2), the general formula (1): the general formula(2)=3:2, a number average molecular weight of 70000, and a weightaverage molecular weight of 150000.

The block copolymerized polyimide solution obtained in the synthesisexample was further diluted with NMP into a block copolymerizedpolyimide solution having a solid content of 10%. To this blockcopolymerized polyimide solution, bis(4-maleimidephenyl)methane (BMI-H,K⋅I Chemical Industry Co., Ltd.) was added so as to have a solid contentproportion of 35 in relation to a solid content proportion of the blockcopolymerized polyimide of 65 (specifically, the solid content weight ofthe bis(4-maleimidephenyl)methane contained in the resin solution: thesolid content weight of the block copolymerized polyimide=35:65), andthe resulting solution was dissolved and mixed at 60° C. for 20 minutesto yield a resin solution. Subsequently, in each of Example A8 andExample B8, to the surface of the ultra-thin copper foil, the resinsolution was applied by using a reverse roll coating machine, dried inan nitrogen atmosphere, at 120° C. for 3 minutes and a 160° C. for 3minutes, and then finally heat treated at 300° C. for 2 minutes, andthus, a copper foil provided with a resin layer was produced. Thethickness of the resin layer was set to be 2 μm.

(Various Evaluations of Surface-Treated Copper Foil and Copper Foil withCarrier)

The surface-treated copper foils and the copper foils with carrierobtained as described above were subjected to various evaluations on thebasis of the following methods.

<Linear Roughness Rz>

For each of the surface-treated copper foils and the copper foils withcarrier of Examples and Comparative Examples, the ten-point averageroughness of the surface-treated surface was measured according to JISB0601-1994 by using the contact surface roughness meter Surfcorder SE-3Cmanufactured by Kosaka Laboratory Ltd. The values of three timesmeasurements were determined by performing the measurement three timesunder the conditions of a measurement reference length of 0.8 mm, anevaluation length of 4 mm, a cut-off value of 0.25 mm, a feed speed of0.1 mm/sec, while in the case of a rolled copper foil, the measurementposition is being varied in the direction (TD) perpendicular to therolling direction, or in the case of an electrolytic copper foil, themeasurement position is being varied in the direction (TD) perpendicularto the traveling direction of the electrolytic copper foil in theproduction apparatus of the electrolytic copper foil.

<Surface Roughness Sz>

The surface roughness (the maximum height of the surface) Sz of thesurface on the surface-treated layer side of each of the surface-treatedcopper foils and the copper foils with carrier was measured according toISO25178, by using a laser microscope (testing apparatus: OLYMPUS LEXTOLS 4000, resolution: XY-0.12 μm, Z-0.0 μm, cut-off: none) manufacturedby Olympus Corp. The measurement area of the observation section was setto be 66524 μm².

<Area Ratio (B/A)>

For each of the surface-treated copper foils and the copper foils withcarrier of Examples and Comparative Examples, the area of the surface onthe surface-treated layer side was measured by a measurement methodbased on a laser microscope. For each of the copper foils, after thesurface treatment, of Examples and Comparative Examples, by using alaser microscope (testing apparatus: OLYMPUS LEXT OLS 4000, resolution:XY-0.12 μm, Z-0.0 μm, cut-off: none) manufactured by Olympus Corp., thethree-dimensional area B in an area A (the surface area obtained in planview) corresponding to 256 μm×256 μm (in the actual data, 66524 μm²) wasmeasured, and the area ratio was calculated by a technique adopting therelation, the three-dimensional area B divided by the two-dimensionalarea A=the area ratio (B/A). The measurement environment temperature forthe three-dimensional area B with the laser microscope was set at 23 to25° C.

For each of the surface-treated copper foils and the copper foils withcarrier of Examples and Comparative Examples, a 20-cm square size of thefollowing resin substrate was prepared, and the resin substrate werelaminated and pressed to each other in such a way that the surface ofthe copper foil, having the surface-treated layer was brought intocontact with the resin substrate. The recommended conditions of thesubstrate maker were adopted for the temperature, the pressure and thetime in the lamination press.

Resin used: GHPL-830MBT of Mitsubishi Gas Chemical Company, Inc.

Next, the surface-treated copper foil on the resin substrate was removedby entire-surface etching under the following etching conditions. Forthe copper foil with carrier on the resin substrate, after peeling thecarrier, the ultra-thin copper layer was removed by entire-surfaceetching under the following etching conditions. The “entire-surfaceetching” as referred to herein means an etching performed until the fullthickness of the copper foil is removed, and the resin is exposed allover the surface.

(Etching conditions) Etching solutions: cupric chloride solution, HClconcentration: 3.5 mol/L, temperature: 50° C., CuCl₂ concentration:regulated so as to give a specific gravity of 1.26.

2. Formation of Surface Profile of Resin Substrate Using ChemicalSolution

As Comparative Example B5, two 100-μm-thick sheets of the resinsubstrate GHPL-830MBT manufactured by Mitsubishi Gas Chemical Company,Inc. were prepared. The two sheets of the substrate were superposed oneach other, and a release layer film was bonded to each side of the setof the two sheets, and the set of the two sheets was subjected tolamination pressing. The recommended conditions of the substrate makerwere adopted for the temperature, the pressure and the time in thelamination press. After completion of lamination pressing, the releaselayer films were removed from the resin substrates, and desmeartreatments A and B and a neutralization treatment were performed underthe following immersion treatment conditions, to form the surfaceprofile of the resin substrate.

(Desmear Treatment Conditions A)

-   -   Desmear treatment solution: 40 g/L KMnO₄, 20 g/L NaOH    -   Treatment temperature: Room temperature    -   Immersion time: 20 minutes    -   Number of rotations of stirrer: 300 rpm

(Desmear Treatment Conditions B)

Desmear treatment solution: 90 g/L KMnO₄, 5 g/L HCl

-   -   Treatment temperature: 49° C.    -   Immersion time: 20 minutes    -   Number of rotations of stirrer: 300 rpm

(Neutralization Treatment Conditions)

-   -   Neutralization treatment solution: L-Ascorbic acid 80 g/L    -   Treatment temperature: Room temperature    -   Immersion time: 3 minutes    -   No stirring

As Comparative Example B6, two 100-μm-thick sheets of the resinsubstrate GHPL-830MBT manufactured by Mitsubishi Gas Chemical Company,Inc. were prepared. The two sheets of the substrate were superposed oneach other, and a release layer film was bonded to each side of the setof the two sheets, and the set of the two sheets was subjected tolamination pressing. The recommended conditions of the substrate makerwere adopted for the temperature, the pressure and the time in thelamination press. After completion of lamination pressing, the releaselayer films were removed from the resin substrates, and desmeartreatments A and B and a neutralization treatment were performed underthe following immersion treatment conditions, to form the surfaceprofile of the resin substrate.

(Desmear Treatment Conditions A)

-   -   Desmear treatment solution: 40 g/L KMnO₄, 20 g/L NaOH    -   Treatment temperature: Room temperature    -   Immersion time: 20 minutes    -   Number of rotations of stirrer: 300 rpm

(Desmear Treatment Conditions B)

-   -   Desmear treatment solution: 90 g/L KMnO₄, 5 g/L HCl    -   Treatment temperature: 49° C.    -   Immersion time: 30 minutes    -   Number of rotations of stirrer: 300 rpm

(Neutralization Treatment Conditions)

-   -   Neutralization treatment solution: L-Ascorbic acid 80 g/l    -   Treatment temperature: Room temperature    -   Immersion time: 3 minutes    -   No stirring

As Comparative Example B9, two 100-μm-thick sheets of the resinsubstrate GHPL-830MBT manufactured by Mitsubishi Gas Chemical Company,Inc. were prepared. The two sheets of the substrate were superposed oneach other, and a release layer film was bonded to each side of the setof the two sheets, and the set of the two sheets was subjected tolamination pressing. The recommended conditions of the substrate makerwere adopted for the temperature, the pressure and the time in thelamination press. After completion of lamination pressing, the releaselayer films were removed from the resin substrates, and on the surfacesof the resin substrate, shower treatments A and B and a neutralizationtreatment were performed under the following treatment conditions, toform the surface profile of the resin substrate.

(Shower Treatment Conditions A)

-   -   Desmear treatment solution: 40 g/L KMnO₄, 20 g/L NaOH    -   Treatment temperature: Room temperature    -   Treatment time: 20 minutes    -   Shower pressure: 0.2 MPa

(Shower Conditions B)

-   -   Desmear treatment solution: 90 g/L KMnO₄, 5 g/L HCl    -   Treatment temperature: 49° C.    -   Treatment time: 20 minutes    -   Shower pressure: 0.2 MPa

(Neutralization Conditions)

-   -   Neutralization treatment solution: L-Ascorbic acid 80 g/L    -   Treatment temperature: Room temperature    -   Immersion time: 3 minutes    -   No stirring

Thus, the formation of the surface profiles of the resin substratesusing chemical solutions was performed.

(Evaluations of Resin Substrates)

The resin substrates of Examples and Comparative Examples having thesurface profiles produced above were subjected to the followingevaluations.

<Linear Roughness Rz>

For each of the etched side surfaces of the resin substrates of Examplesand Comparative Examples, the ten-point average roughness was measuredaccording to JIS B0601-1994 by using the contact surface roughness meterSurfcorder SE-3C manufactured by Kosaka Laboratory Ltd. The values ofthree times measurements were determined by performing the measurementthree times under the conditions of a measurement reference length of0.8 mm, an evaluation length of 4 mm, a cut-off value of 0.25 mm, a feedspeed of 0.1 mm/sec.

<Surface Roughness Sz>

For each of the etched side surfaces of the resin substrates of Examplesand Comparative Examples, by using a laser microscope (testingapparatus: OLYMPUS LEXT OLS 4000, resolution: XY-0.12 μm, Z-0.0 μm,cut-off: none) manufactured by Olympus Corp., the surface roughness (themaximum height of the surface) Sz was measured according to ISO25178.The measurement area of the observation section was set to be 66524 μm².

<Area Ratio (B/A)>

For each of the etched side surfaces of the resin substrates of Examplesand Comparative Examples, by using a laser microscope (testingapparatus: OLYMPUS LEXT OLS 4000, resolution: XY-0.12 μm, Z-0.0 μm,cut-off: none) manufactured by Olympus Corp., the three-dimensional areaB in an area A (the surface area obtained in plan view) corresponding to256 μm×256 μm (in the actual data, 66524 μm²) was measured, and the arearatio was calculated by a technique adopting the relation, thethree-dimensional area B divided by the two-dimensional area A=the arearatio (B/A). The measurement environment temperature for thethree-dimensional area B with the laser microscope was set at 23 to 25°C.

<Black Area Rate>

For each of the etched side surfaces of the resin substrates of Examplesand Comparative Examples, by using a scanning electron microscope (SEM),photography was performed with an acceleration voltage set at 15 kV.During photography, contrast and brightness were regulated so as for thecontours of the holes in the whole observation field to be clearly seen.Photography was performed in the state in which the contours of theholes were able to be observed, but not in the state in which the entirephotograph was white or black. When photography is performed in a statein which the contours of the holes can be observed, but not in the statein which the entire photograph is white or black, the black area rates(%) of the photographs concerned give nearly the same values. Ablack-white image processing was applied to the taken photographs (SEMimages (magnification of 30 k (30000)), by using Photo Shop 7.0software, and thus, the black area rates (%) were determined. The blackarea rate (%) was determined as the rate of the black area in relationto the observation area (the sum of the white area and the black area)at the threshold value of 128 set by selecting “Histogram” of “Image”found in Photo Shop 7.0.

<Average Value of Diameters of Holes>

For each of the etched side surfaces of the resin substrates of Examplesand Comparative Examples, from the SEM image (×6000 to ×30000), by thesegment method, the diameters of the holes were measured longitudinally,transversely and obliquely, and the average value of N=3 of these valueswas calculated.

<Peel Strength>

The etched surface of each of the resin substrates (entire-surfaceetched substrates) was provided with a catalyst for depositingelectroless copper, and was subjected to an electroless copper platingunder the following conditions by using the KAP-8 bath manufactured byKanto Kasei Co., Ltd. The thickness of the obtained electroless copperplating was 0.5 μm.

CuSO₄ concentration: 0.06 mol/L, HCHO concentration: 0.5 mol/L, EDTAconcentration: 0.12 mol/L, pH 12.5, additive: 2,2′-bipyridyl, additiveconcentration: 10 mg/L, surfactant: REG-1000, surfactant concentration:500 mg/L

Next, on the electroless copper plating, further electrolytic platingwas performed by using the following electrolyte. The copper thickness(total thickness of electroless plating and electrolytic plating) was 12μm.

Simple copper sulfate electrolyte: Cu concentration: 100 g/L, H₂SO₄concentration: 80 g/L

A 10-mm-wide copper circuit was formed by wet etching on the laminatewith copper plating formed as described above by subjecting the resinsubstrate (entire-surface etched substrate) to electroless copperplating and electrolytic copper plating so as to have a copper layerthickness of 12 μm. According to JIS-C-6481, the strength in the case ofpeeling this copper circuit at an angle of 90 degrees was measured to betaken as the peel strength.

<Fine Wiring Formability>

On the laminate with copper plating formed as described above bysubjecting the resin substrate (entire-surface etched substrate) toelectroless copper plating and electrolytic copper plating so as to havea copper layer thickness of 12 μm, circuits having L(line)/S(space)=15μm/15 μm and 10 μm/10 μm, respectively, were formed by processing theplating copper by etching. In this case, the fine wirings formed on theresin substrate was visually observed, and the case where the detachmentof the circuit, the shortening between the circuits (abnormal depositionof copper between circuits) and the deficit of the circuit were notfound was marked as acceptable (circle).

Tables 1 and 4 show the production conditions of the above-describedcopper foils used to obtain the surface profiles of the substrates bytransferring the profiles of the surfaces of the copper foils to thesurfaces of the substrates, in Examples A1 to A11, Comparative ExamplesA1 to A4, Examples B1 to B12, and Comparative Examples B1 to B4.

Tables 2 and 5 show the above-described evaluation results of thesurface profiles of the substrates.

Tables 3 and 6 show the above-described evaluation results of thesurface profiles of the copper foils giving the surface profiles of thesubstrates.

TABLE 1 Surface treatment Raw foil Rust- Application of (correspondingto copper Treated side Roughening Barrier preventing silane couplingSample foil bulk layer) surface treatment treatment treatment agentExample A1 Ultra-thin raw foil with Ultra-thin Fine Not applied AppliedApplied carrier copper roughening (3) surface Example A2 Ultra-thin rawfoil with Ultra-thin Fine Not applied Applied Applied carrier copperroughening (4) surface Example A3 Ultra-thin raw foil with Ultra-thinFine Zn•Ni Applied Applied carrier copper roughening (1) surface ExampleA4 Ultra-thin raw foil with Ultra-thin Fine Not applied Applied Appliedcarrier copper roughening (2) surface Example A5 Double flat sided Msurface Fine Not applied Applied Applied electrolytic raw copper foil(high gloss roughening (3) surface) Example A6 Double flat sided Msurface Fine Brass Applied Applied electrolytic raw copper foil (highgloss roughening (1) surface) Example A7 Common electrolytic raw Ssurface Not applied Not applied Applied Applied foil Example A8Ultra-thin raw foil with Ultra-thin Fine Not applied Applied Appliedcarrier (with resin) copper roughening (4) surface Example A9 Ultra-thinraw foil with Ultra-thin Fine Not applied Applied Applied carrier copperroughening (5) surface Example Ultra-thin raw foil with Ultra-thin FineNot applied Applied Applied A10 carrier copper roughening (6) surfaceExample Ultra-thin raw foil with Ultra-thin Fine Not applied AppliedApplied A11 carrier copper roughening (7) surface Comparative Commonelectrolytic raw M surface Fine Zn•Ni Applied Applied Example A1 foilroughening (1) Comparative Common electrolytic raw M surface SphericalBrass Applied Applied Example A2 foil roughening (ordinary) ComparativeCommon electrolytic raw S surface Spherical Brass Applied AppliedExample A3 foil roughening (ordinary) Comparative Ultra-thin raw foilwith Ultra-thin Not applied Not applied Applied Applied Example A4carrier copper surface

TABLE 2 Contact surface roughness meter Laser roughness meter AverageLinear Surface Observation Black value of Fine wiring Thickness ofroughness roughness section Measured Surface area diameters formabilitycopper foil Rz Sz surface area surface area area ratio rate of holesPeel strength L/S = L/S = (μm) (μm) (μm) A (μm2) B (μm2) B/A (%) (μm)(kg/cm) Evaluation 15/15 10/10 Example A1 3 0.8 1.65 66524 67490 1.014519 0.09 0.64 ◯ ◯ ◯ Example A2 3 1.1 2.24 66524 74186 1.1152 28 0.39 0.72◯ ◯ ◯ Example A3 3 1.1 2.65 66524 78503 1.1801 38 0.18 0.78 ◯ ◯ ◯Example A4 3 1.6 3.39 66524 83369 1.2532 50 0.76 0.53 ◯ ◯ X Example A512 1.2 1.83 66524 68101 1.0237 31 0.11 0.68 ◯ ◯ ◯ Example A6 12 1.0 2.9566524 85124 1.2796 34 0.56 0.80 ◯ ◯ ◯ Example A7 12 1.6 2.05 66524 682581.0261 25 0.03 0.50 ◯ ◯ ◯ Example A8 3 (with 1.1 2.32 66524 73698 1.107827 0.38 0.95 ◯ ◯ ◯ resin) Example A9 1.5 0.8 0.97 66524 71846 1.0800 90.20 0.52 ◯ ◯ ◯ Example A10 2 1.6 5.12 66524 100518 1.5110 49 0.89 0.81◯ ◯ X Example A11 5 0.8 1.05 66524 67123 1.0090 9 0.35 0.52 ◯ ◯ ◯Comparative 12 2.5 7.03 66524 117312 1.7635 54 3.40 0.83 ◯ X X ExampleA1 Comparative 12 2.4 8.53 66524 128211 1.9273 62 2.13 0.80 ◯ X XExample A2 Comparative 12 1.6 5.25 66524 101589 1.5271 58 1.82 0.40 X ◯◯ Example A3 Comparative 3 0.3 0.78 66524 66590 1.0010 0 0.00 0.25 X ◯ ◯Example A4

TABLE 3 Contact surface Laser roughness meter roughness meter SurfaceObservation Thickness of Linear roughness roughness section surfaceMeasured Surface area copper foil Rz Sz area surface area ratio (μm)(μm) (μm) A (μm2) B (μm2) B/A Example A1 3 0.8 2.51 66524 77819 1.1698Example A2 3 1.0 3.23 66524 79589 1.1964 Example A3 3 1.0 3.59 6652482498 1.2401 Example A4 3 1.6 3.40 66524 87160 1.3102 Example A5 12 0.62.28 66524 75913 1.1411 Example A6 12 1.5 4.82 66524 110975 1.6682Example A7 12 1.6 2.76 66524 72121 1.0841 Example A8 3 (with resin) 1.03.18 66524 78966 1.1870 Example A9 1.5 0.7 1.92 66524 74706 1.1230Example A10 2 1.7 6.72 66524 107769 1.6200 Example A11 5 0.7 2.80 6652468613 1.0314 Comparative 12 2.5 7.95 66524 144589 2.1735 Example A1Comparative 12 3.6 9.79 66524 157818 2.3723 Example A2 Comparative 122.0 6.24 66524 134521 2.0221 Example A3 Comparative 3 0.8 1.20 6652466925 1.0060 Example A4

TABLE 4 Surface treatment Raw foil Rust- Application of (correspondingto copper Treated side Roughening Barrier preventing silane couplingSample foil bulk layer) surface treatment treatment treatment agentExample B1 Ultra-thin raw foil with Ultra-thin copper Fine rougheningNot applied Applied Applied carrier surface (3) Example B2 Ultra-thinraw foil with Ultra-thin copper Fine roughening Not applied AppliedApplied carrier surface (4) Example B3 Ultra-thin raw foil withUltra-thin copper Fine roughening Zn•Ni Applied Applied carrier surface(1) Example B4 Ultra-thin raw foil with Ultra-thin copper Fineroughening Not applied Applied Applied carrier surface (2) Example B5Double flat sided M surface (high Fine roughening Not applied AppliedApplied electrolytic raw copper gloss surface) (3) foil Example B6Double flat sided M surface (high Fine roughening Brass Applied Appliedelectrolytic raw copper gloss surface) (1) foil Example B7 Commonelectrolytic S surface Not applied Not applied Applied Applied raw foilExample B8 Ultra-thin raw foil with Ultra-thin copper Fine rougheningNot applied Applied Applied carrier (with resin) surface (4) Example B10Ultra-thin raw foil with Ultra-thin copper Fine roughening Not appliedApplied Applied carrier surface (5) Example B11 Ultra-thin raw foil withUltra-thin copper Fine roughening Not applied Applied Applied carriersurface (6) Example B12 Ultra-thin raw foil with Ultra-thin copper Fineroughening Not applied Applied Applied carrier surface (7) ComparativeCommon electrolytic M surface Fine roughening Zn•Ni Applied AppliedExample B1 raw foil (1) Comparative Common electrolytic M surfaceSpherical Brass Applied Applied Example B2 raw foil roughening(ordinary) Comparative Common electrolytic S surface Spherical BrassApplied Applied Example B3 raw foil roughening (ordinary) ComparativeUltra-thin raw foil with Ultra-thin copper Not applied Not applied Notapplied Applied Example B4 carrier surface

TABLE 5 Contact surface roughness meter Laser roughness meter AverageLinear Surface Observation Black value of Fine wiring Thickness ofroughness roughness section surface Measured Surface area diametersformability copper foil Rz Sz area surface area area ratio rate of holesPeel strength L/S = L/S = (μm) (μm) (μm) A (μm²) B (μm²) B/A (%) (μm)(kg/cm) Evaluation 15/15 10/10 Example B1 3 0.8 1.65 66524 67490 1.014519 0.09 0.64 ◯ ◯ ◯ Example B2 3 1.1 2.24 66524 74186 1.1152 28 0.39 0.72◯ ◯ ◯ Example B3 3 1.1 2.65 66524 78503 1.1801 38 0.18 0.78 ◯ ◯ ◯Example B4 3 1.6 3.39 66524 83369 1.2532 50 0.76 0.53 ◯ ◯ X Example B512 1.2 1.83 66524 68101 1.0237 31 0.11 0.68 ◯ ◯ ◯ Example B6 12 1.0 2.9566524 85124 1.2796 34 0.56 0.80 ◯ ◯ ◯ Example B7 12 1.6 2.05 66524 682581.0261 25 0.03 0.50 ◯ ◯ ◯ Example B8 3 (with 1.1 2.32 66524 73698 1.107827 0.38 0.95 ◯ ◯ ◯ resin) Example B9 (No use of 0.8 1.56 66524 678251.0196 20 0.07 0.58 ◯ ◯ ◯ copper foil) Example 1.5 0.8 0.97 66524 718461.0800 9 0.20 0.52 ◯ ◯ ◯ B10 Example 2 1.6 5.12 66524 100518 1.5110 490.89 0.81 ◯ ◯ X B11 Example 5 0.8 1.05 66524 67123 1.0090 9 0.35 0.52 ◯◯ ◯ B12 Comparative 12 2.5 7.03 66524 117312 1.7635 54 3.40 0.83 ◯ X XExample B1 Comparative 12 2.4 8.53 66524 128211 1.9273 62 2.13 0.80 ◯ XX Example B2 Comparative 12 1.6 5.25 66524 101589 1.5271 58 1.82 0.40 X◯ ◯ Example B3 Comparative 3 0.3 0.78 66524 66590 1.0010 0 0.00 0.25 X ◯◯ Example B4 Comparative (No use of 0.8 0.96 66524 66829 1.0046 8 0.0050.42 X ◯ ◯ Example B5 copper foil) Comparative (No use of 0.8 0.91 6652466721 1.0030 10 0.003 0.40 X ◯ ◯ Example B6 copper foil)

TABLE 6 Contact surface Laser roughness meter roughness meter SurfaceObservation Measured Thickness of Linear roughness section surfacesurface Surface copper foil roughness Rz Sz area area area ratio (μm)(μm) (μm) A (μm²) B (μm²) B/A Example B1 3 0.8 2.51 66524 77819 1.1698Example B2 3 1.0 3.23 66524 79589 1.1964 Example B3 3 1.0 3.59 6652482498 1.2401 Example B4 3 1.6 3.40 66524 87160 1.3102 Example B5 12 0.62.28 66524 75913 1.1411 Example B6 12 1.5 4.82 66524 110975 1.6682Example B7 12 1.6 2.76 66524 72121 1.0841 Example B8 3 (with resin) 1.03.18 66524 78966 1.1870 Example B10 1.5 0.7 1.92 66524 74706 1.1230Example B11 2 1.7 6.72 66524 107769 1.6200 Example B12 5 0.7 2.24 6652468613 1.0314 Comparative 12 2.5 7.95 66524 144589 2.1735 Example B1Comparative 12 3.6 9.79 66524 157818 2.3723 Example B2 Comparative 122.0 6.24 66524 134521 2.0221 Example B3 Comparative 3 0.8 1.20 6652466925 1.0060 Example B4 Note: The data of the roughness and the surfacearea ratio of the copper foil of Example B8 are the data of the copperfoil before application of the resin.

(Evaluation Results)

Each of Examples A1 to A11 had a satisfactory fine wiring formability,and moreover, exhibited a satisfactory peel strength.

Each of the copper foils of Comparative Examples A1 to A4 had thesurface roughness Sz of the surface of the surface-treated layer fallingoutside the range from 2 to 6 μm, and accordingly had the surfaceroughness Sz in the surface profile of the substrate falling outside therange from 1 to 5 μm to result in a poor fine wiring formability or apoor peel strength. Each of the copper foils of Comparative Examples A1to A4 had the ratio B/A of the three-dimensional surface area B to thetwo-dimensional surface area A of the surface of the surface-treatedlayer falling outside the range from 1.05 to 1.8, and accordingly theratio B/A concerned in the surface profile of the substrate fell outsidethe range from 1.01 to 1.5 to result in a poor fine wiring formabilityor a poor peel strength. Each of the surface profiles of the substratesof Comparative Examples A1 to A4 had a black area rate of the surfacefalling outside the range from 10 to 50%, and an average value of thediameters of the holes of the surface falling outside the range from0.03 to 1.0 μm, to result in a poor fine wiring formability or a poorpeel strength.

From the evaluation results of Examples and Comparative Examples, it hasbeen verified that the numerical values of Rz of the surface of thecopper foil and the surface of the substrate are not particularlyrelated to the combination of a satisfactory fine wiring formability anda satisfactory peel strength.

Each of the substrates of Examples B1 to B12 had a satisfactory finewiring formability, and moreover exhibited a satisfactory peel strength.

Each of the substrates of Comparative Examples B1 to B6 had a surfaceroughness Sz of the surface falling outside the range from 1 to 5 μm, toresult in a poor fine wiring formability or a poor peel strength. Eachof the substrates of Comparative Examples B1 to B4 had the ratio B/A ofthe three-dimensional surface area B to the two-dimensional surface areaA of the surface ratio B/A of the three-dimensional surface area B tothe two-dimensional surface area A of the surface falling outside therange from 1.01 to 1.5, to result in a poor fine wiring formability or apoor peel strength. Each of the substrates of Comparative Examples B1 toB6 had both or either of a black area rate of the surface fallingoutside the range from 10 to 50% and the average value of the diametersof the holes of the surface falling outside the range from 0.03 to 1.0μm, to result in a poor fine wiring formability or a poor peel strength.

From the evaluation results of Examples and Comparative Examples, it hasbeen verified that the numerical value of Rz of the surface of thesubstrate is not particularly related to the combination of asatisfactory fine wiring formability and a satisfactory peel strength.

FIGS. 3A, 3B, 3C, 3D and 3E how the SEM images (×30000) of the copperfoil-treated surfaces of Examples A1, A2, A3, A5 and A6, respectively.

FIGS. 4A and 4B show the SEM images (×6000) of the copper foil-treatedsurfaces of Comparative Examples A1 and A2.

FIGS. 5(A), 5(B), 5(C), 5(D) and 5(E) show the SEM images (×30000) ofthe surfaces of the resin substrates of Examples A1(B1), A2(B2), A3(B3),A5(B5) and A6(B6), respectively.

FIGS. 6(A) and 6(B) show the SEM images (×6000) of the surfaces of theresin substrates of Comparative Examples A1(B1) and A2(B2),respectively.

1. A substrate prepared by bonding a surface-treated copper foil whereina surface treated layer is formed on a copper foil, wherein the surfaceroughness Sz of the surface of the surface-treated layer is 2 to 6 μm,the surface-treated copper foil optionally having a resin layer on thesurface-treated layer, via the surface-treated layer side thereof, to asubstrate, and by removing the surface-treated copper foil, or asubstrate prepared by bonding a copper foil with carrier, the copperfoil with carrier comprising a carrier, an intermediate layer and anultra-thin copper layer in this order, the ultra-thin copper layer beinga surface-treated copper foil wherein a surface treated layer is formedon a copper foil, wherein the surface roughness Sz of the surface of thesurface-treated layer is 2 to 6 μm and optionally having a resin layer,via the ultra-thin copper layer side thereof, to a substrate, and byremoving the carrier from the copper foil with carrier and removing theultra-thin copper layer which is the surface-treated copper foil,wherein at least one of the following (1) to (3) is satisfied: (1) thesurface roughness Sz of the surface, on the copper foil removal side, ofthe substrate is 1 to 5 μm, (2) the ratio B/A of the three-dimensionalsurface area B to the two-dimensional surface area A of surface, on thecopper foil removal side of the substrate, is 1.01 to 1.5, or (3) theblack area rate of the surface, on the copper foil removal side, of thesubstrate is 10 to 50%, and the average value of the diameters of theholes of the surface, on the copper foil removal side of the substrate,is 0.03 to 1.0 μm.
 2. A resin substrate wherein at least one of thefollowing (1) to (3) is satisfied: (1) a surface roughness Sz of thesurface of the resin substrate is 1 to 5 μm, (2) the ratio B/A of thethree-dimensional surface area B to the two-dimensional surface area Aof the surface of the resin substrate is 1.01 to 1.5, or (3) the blackarea rate of the surface of the resin substrate is 10 to 50%, and theaverage value of the diameters of the holes of the surface of the resinsubstrate is 0.03 to 1.0 μm.
 3. A method for producing a printed wiringboard comprising: a step of preparing the resin substrate according toclaim 2, and a step of forming a circuit on the surface of the resinsubstrate.
 4. A method for producing a printed wiring board comprising:a step of preparing the resin substrate according to claim 2, and a stepof producing a printed wiring board with the resin substrate.
 5. Acopper clad laminate comprising the resin substrate according to claim2.
 6. A method for producing a printed wiring board, comprising: a stepof preparing a surface-treated copper foil, or a copper foil withcarrier comprising a carrier, an intermediate layer and an ultra-thincopper layer in this order, and a resin substrate; a step of laminatingthe surface-treated copper foil, via the surface-treated layer sidethereof, on the resin substrate, or a step of laminating the copper foilwith carrier, via the ultra-thin copper layer side thereof, on the resinsubstrate, and then peeling the carrier of the copper foil with carrier;a step of obtaining the resin substrate according to claim 2 by removingthe surface-treated copper foil or removing the ultra-thin copper layeron the resin substrate; and a step of forming a circuit on the surfaceof the resin substrate with the surface-treated copper foil or theultra-thin copper layer removed therefrom.
 7. A method for producing aprinted wiring board, comprising: a step of forming a copper cladlaminate by laminating a surface-treated copper foil via thesurface-treated layer side thereof, on the resin substrate according toclaim 2, or by laminating a copper foil with carrier comprising acarrier, an intermediate layer and an ultra-thin copper layer in thisorder, via the ultra-thin copper layer side thereof, on the resinsubstrate according to claim 42, and then, peeling the carrier of thecopper foil with carrier; and a step of subsequently forming a circuitby a semi-additive method, a subtractive method, a partly additivemethod or a modified semi-additive method.
 8. A method for producing aprinted wiring board, comprising: a step of preparing a metal foil withcircuit formed on the surface thereof, or a step of forming a circuit onthe surface on the ultra-thin copper layer side of a copper foil withcarrier constituted by laminating a carrier, an intermediate layer andan ultra-thin copper layer in this order; a step of forming the resinsubstrate according to claim 2 on the surface of the metal foil, or onthe surface on the ultra-thin copper layer side of a copper foil withcarrier, so as for the circuit to be embedded; a step of forming acircuit on the resin layer; and a step of exposing the circuit formed onthe surface of the metal foil or on the surface of the copper foil withcarrier and embedded in the resin substrate by removing the metal foilor the copper foil with carrier.
 9. A surface-treated copper foil,wherein at least one of the following (1) to (3) is satisfied: (1) whenthe surface-treated copper foil is bonded, via the surface-treated layerside thereof, to a resin substrate and the surface-treated copper foilis removed, the surface roughness Sz of the surface on the copper foilremoval side of the resin substrate is 1 to 3 μm, (2) when thesurface-treated copper foil is bonded, via the surface-treated layerside thereof, to a resin substrate and the surface-treated copper foilis removed, the black area rate of the surface on the copper foilremoval side of the resin substrate is 10 to 45%, (3) when thesurface-treated copper foil is bonded, via the surface-treated layerside thereof, to a resin substrate and the surface-treated copper foilis removed, the average value of the diameters of holes of the surfaceon the copper foil removal side of the resin substrate is 0.03 to 0.7μm.